diff --git a/.gitignore b/.gitignore
index 0281ad4..1f89459 100644
--- a/.gitignore
+++ b/.gitignore
@@ -248,3 +248,5 @@ DerivedData
 compile_commands.json
 CMakeScripts
 UEFITool/qrc_uefitool.cpp
+XcodeQT5
+XcodeQT6
diff --git a/UEFITool/ffsfinder.cpp b/UEFITool/ffsfinder.cpp
index ceb4a06..19b9653 100644
--- a/UEFITool/ffsfinder.cpp
+++ b/UEFITool/ffsfinder.cpp
@@ -29,7 +29,12 @@ USTATUS FfsFinder::findHexPattern(const UModelIndex & index, const UByteArray &
 
     bool hasChildren = (model->rowCount(index) > 0);
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         findHexPattern(index.child(i, index.column()), hexPattern, mode);
+#else
+        findHexPattern(index.model()->index(i, index.column(), index), hexPattern, mode);
+#endif
+
     }
 
     UByteArray data;
@@ -49,9 +54,22 @@ USTATUS FfsFinder::findHexPattern(const UModelIndex & index, const UByteArray &
     }
 
     UString hexBody = UString(data.toHex());
+#if QT_VERSION_MAJOR >= 6
+    QRegularExpression regexp = QRegularExpression(UString(hexPattern));
+    regexp.setPatternOptions((QRegularExpression::PatternOptions)0x1);
+    QRegularExpressionMatch regexpmatch;
+
+    INT32 offset = 0;
+    while ((offset = (INT32)hexBody.indexOf(regexp, (qsizetype)offset, &regexpmatch)) != -1)
+    {
+#else
     QRegExp regexp = QRegExp(UString(hexPattern), Qt::CaseInsensitive);
+
     INT32 offset = regexp.indexIn(hexBody);
+
     while (offset >= 0) {
+#endif
+
         if (offset % 2 == 0) {
             // For patterns that cross header|body boundary, skip patterns entirely located in body, since
             // children search above has already found them.
@@ -64,7 +82,12 @@ USTATUS FfsFinder::findHexPattern(const UModelIndex & index, const UByteArray &
                     index);
             }
         }
+
+#if QT_VERSION_MAJOR >= 6
+        offset += 1;
+#else
         offset = regexp.indexIn(hexBody, offset + 1);
+#endif
     }
 
     return U_SUCCESS;
@@ -80,7 +103,11 @@ USTATUS FfsFinder::findGuidPattern(const UModelIndex & index, const UByteArray &
 
     bool hasChildren = (model->rowCount(index) > 0);
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         findGuidPattern(index.child(i, index.column()), guidPattern, mode);
+#else
+        findGuidPattern(index.model()->index(i, index.column(), index), guidPattern, mode);
+#endif
     }
 
     UByteArray data;
@@ -121,8 +148,19 @@ USTATUS FfsFinder::findGuidPattern(const UModelIndex & index, const UByteArray &
     if (hexPattern.count('.') == hexPattern.length())
         return U_SUCCESS;
 
+#if QT_VERSION_MAJOR >= 6
+    QRegularExpression regexp((QString)UString(hexPattern));
+    regexp.setPatternOptions((QRegularExpression::PatternOptions)0x1);
+    QRegularExpressionMatch regexpmatch;
+
+    INT32 offset = 0;
+    offset = (INT32)hexBody.indexOf(regexp, (qsizetype)offset, &regexpmatch);
+#else
     QRegExp regexp(UString(hexPattern), Qt::CaseInsensitive);
+
     INT32 offset = regexp.indexIn(hexBody);
+#endif
+
     while (offset >= 0) {
         if (offset % 2 == 0) {
             msg(UString("GUID pattern \"") + UString(guidPattern)
@@ -132,7 +170,12 @@ USTATUS FfsFinder::findGuidPattern(const UModelIndex & index, const UByteArray &
                 + usprintf(" at %s-offset %02Xh", mode == SEARCH_MODE_BODY ? "body" : "header", offset / 2),
                 index);
         }
+
+#if QT_VERSION_MAJOR >= 6
+        offset = (INT32)hexBody.indexOf(regexp, (qsizetype)offset + 1, &regexpmatch);
+#else
         offset = regexp.indexIn(hexBody, offset + 1);
+#endif
     }
 
     return U_SUCCESS;
@@ -148,7 +191,11 @@ USTATUS FfsFinder::findTextPattern(const UModelIndex & index, const UString & pa
 
     bool hasChildren = (model->rowCount(index) > 0);
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         findTextPattern(index.child(i, index.column()), pattern, mode, unicode, caseSensitive);
+#else
+        findTextPattern(index.model()->index(i, index.column(), index), pattern, mode, unicode, caseSensitive);
+#endif
     }
 
     UByteArray body;
@@ -167,12 +214,16 @@ USTATUS FfsFinder::findTextPattern(const UModelIndex & index, const UString & pa
 
     UString data;
     if (unicode)
-        data = UString::fromUtf16((const ushort*)body.constData(), body.length() / 2);
+#if QT_VERSION_MAJOR >= 6
+        data = UString::fromUtf16((const char16_t*)body.constData(), (int)(body.length() / 2));
+#else
+        data = UString::fromUtf16((const ushort*)body.constData(), (int)(body.length() / 2));
+#endif
     else
         data = UString::fromLatin1((const char*)body.constData(), body.length());
 
     int offset = -1;
-    while ((offset = data.indexOf(pattern, offset + 1, caseSensitive)) >= 0) {
+    while ((offset = (int)data.indexOf(pattern, (int)(offset + 1), caseSensitive)) >= 0) {
 
         msg((unicode ? UString("Unicode") : UString("ASCII")) + UString(" text \"") + UString(pattern)
             + UString("\" in ") + model->name(model->parent(index))
diff --git a/UEFITool/ffsfinder.h b/UEFITool/ffsfinder.h
index b88866b..652cc76 100644
--- a/UEFITool/ffsfinder.h
+++ b/UEFITool/ffsfinder.h
@@ -15,7 +15,12 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #define FFSFINDER_H
 
 #include <vector>
+
+#if QT_VERSION_MAJOR >= 6
+#include <QRegularExpression>
+#else
 #include <QRegExp>
+#endif
 
 #include "../common/ubytearray.h"
 #include "../common/ustring.h"
diff --git a/UEFITool/hexspinbox.cpp b/UEFITool/hexspinbox.cpp
index bb409b8..587ce30 100644
--- a/UEFITool/hexspinbox.cpp
+++ b/UEFITool/hexspinbox.cpp
@@ -15,7 +15,11 @@
 #include <QDebug>
 
 HexSpinBox::HexSpinBox(QWidget *parent) :
+#if QT_VERSION_MAJOR >= 6
+QSpinBox(parent), validator(QRegularExpression("0x([0-9a-fA-F]){1,8}"))
+#else
 QSpinBox(parent), validator(QRegExp("0x([0-9a-fA-F]){1,8}"))
+#endif
 {
     this->setRange(INT_MIN, INT_MAX);
     this->setPrefix("0x");
diff --git a/UEFITool/hexspinbox.h b/UEFITool/hexspinbox.h
index 1304e88..51a4180 100644
--- a/UEFITool/hexspinbox.h
+++ b/UEFITool/hexspinbox.h
@@ -15,7 +15,12 @@
 #define HEXSPINBOX_H
 
 #include <QSpinBox>
+
+#if QT_VERSION_MAJOR >= 6
+#include <QRegularExpressionValidator>
+#else
 #include <QRegExpValidator>
+#endif
 
 class HexSpinBox : public QSpinBox
 {
@@ -30,7 +35,11 @@ protected:
     QString textFromValue(int value) const;
 
 private:
+#if QT_VERSION_MAJOR >= 6
+    QRegularExpressionValidator validator;
+#else
     QRegExpValidator validator;
+#endif
 };
 
 #endif // HEXSPINBOX_H
diff --git a/UEFITool/icons/uefitool.icns b/UEFITool/icons/uefitool.icns
index a332b70..5bd61f4 100644
Binary files a/UEFITool/icons/uefitool.icns and b/UEFITool/icons/uefitool.icns differ
diff --git a/UEFITool/qhexedit2/chunks.cpp b/UEFITool/qhexedit2/chunks.cpp
index a4e420b..80d3d86 100644
--- a/UEFITool/qhexedit2/chunks.cpp
+++ b/UEFITool/qhexedit2/chunks.cpp
@@ -95,11 +95,11 @@ QByteArray Chunks::data(qint64 pos, qint64 maxSize, QByteArray *highlighted)
                     count = maxSize;
                 if (count > 0)
                 {
-                    buffer += chunk.data.mid(chunkOfs, (int)count);
+                    buffer += chunk.data.mid((int)chunkOfs, (int)count);
                     maxSize -= count;
                     pos += count;
                     if (highlighted)
-                        *highlighted += chunk.dataChanged.mid(chunkOfs, (int)count);
+                        *highlighted += chunk.dataChanged.mid((int)chunkOfs, (int)count);
                 }
             }
         }
@@ -176,7 +176,7 @@ qint64 Chunks::indexOf(const QByteArray &ba, qint64 from)
     for (qint64 pos=from; (pos < _size) && (result < 0); pos += BUFFER_SIZE)
     {
         buffer = data(pos, BUFFER_SIZE + ba.size() - 1);
-        int findPos = buffer.indexOf(ba);
+        int findPos = (int)buffer.indexOf(ba);
         if (findPos >= 0)
             result = pos + (qint64)findPos;
     }
@@ -194,7 +194,7 @@ qint64 Chunks::lastIndexOf(const QByteArray &ba, qint64 from)
         if (sPos < 0)
             sPos = 0;
         buffer = data(sPos, pos - sPos);
-        int findPos = buffer.lastIndexOf(ba);
+        int findPos = (int)buffer.lastIndexOf(ba);
         if (findPos >= 0)
             result = sPos + (qint64)findPos;
     }
@@ -214,8 +214,8 @@ bool Chunks::insert(qint64 pos, char b)
     else
         chunkIdx = getChunkIndex(pos);
     qint64 posInBa = pos - _chunks[chunkIdx].absPos;
-    _chunks[chunkIdx].data.insert(posInBa, b);
-    _chunks[chunkIdx].dataChanged.insert(posInBa, char(1));
+    _chunks[chunkIdx].data.insert((int)posInBa, b);
+    _chunks[chunkIdx].dataChanged.insert((int)posInBa, char(1));
     for (int idx=chunkIdx+1; idx < _chunks.size(); idx++)
         _chunks[idx].absPos += 1;
     _size += 1;
@@ -241,8 +241,8 @@ bool Chunks::removeAt(qint64 pos)
         return false;
     int chunkIdx = getChunkIndex(pos);
     qint64 posInBa = pos - _chunks[chunkIdx].absPos;
-    _chunks[chunkIdx].data.remove(posInBa, 1);
-    _chunks[chunkIdx].dataChanged.remove(posInBa, 1);
+    _chunks[chunkIdx].data.remove((int)posInBa, 1);
+    _chunks[chunkIdx].dataChanged.remove((int)posInBa, 1);
     for (int idx=chunkIdx+1; idx < _chunks.size(); idx++)
         _chunks[idx].absPos -= 1;
     _size -= 1;
diff --git a/UEFITool/qhexedit2/qhexedit.cpp b/UEFITool/qhexedit2/qhexedit.cpp
index 9ce21a0..bc1612a 100644
--- a/UEFITool/qhexedit2/qhexedit.cpp
+++ b/UEFITool/qhexedit2/qhexedit.cpp
@@ -408,7 +408,13 @@ QString QHexEdit::selectionToReadableString()
 void QHexEdit::setFont(const QFont &font)
 {
     QWidget::setFont(font);
+
+#if ((QT_VERSION_MINOR >= 11) && (QT_VERSION_MAJOR == 5)) || (QT_VERSION_MAJOR >= 6)
+    _pxCharWidth = fontMetrics().horizontalAdvance('2');
+#else
     _pxCharWidth = fontMetrics().width(QLatin1Char('2'));
+#endif
+
     _pxCharHeight = fontMetrics().height();
     _pxGapAdr = _pxCharWidth / 2;
     _pxGapAdrHex = _pxCharWidth;
@@ -573,7 +579,7 @@ void QHexEdit::keyPressEvent(QKeyEvent *event)
         {
             QByteArray ba = _chunks->data(getSelectionBegin(), getSelectionEnd() - getSelectionBegin()).toHex();
             for (qint64 idx = 32; idx < ba.size(); idx +=33)
-                ba.insert(idx, "\n");
+                ba.insert((int)idx, "\n");
             QClipboard *clipboard = QApplication::clipboard();
             clipboard->setText(ba);
             if (_overwriteMode)
@@ -596,7 +602,7 @@ void QHexEdit::keyPressEvent(QKeyEvent *event)
             QByteArray ba = QByteArray().fromHex(clipboard->text().toLatin1());
             if (_overwriteMode)
             {
-                ba = ba.left(std::min<qint64>(ba.size(), (_chunks->size() - _bPosCurrent)));
+                ba = ba.left((int)std::min<qint64>(ba.size(), (_chunks->size() - _bPosCurrent)));
                 replace(_bPosCurrent, ba.size(), ba);
             }
             else
@@ -746,7 +752,7 @@ void QHexEdit::keyPressEvent(QKeyEvent *event)
     {
         QByteArray ba = _chunks->data(getSelectionBegin(), getSelectionEnd() - getSelectionBegin()).toHex();
         for (qint64 idx = 32; idx < ba.size(); idx += 33)
-            ba.insert(idx, "\n");
+            ba.insert((int)idx, "\n");
 		if(_upperCase)
 			ba = ba.toUpper();
         QClipboard *clipboard = QApplication::clipboard();
@@ -875,7 +881,7 @@ void QHexEdit::paintEvent(QPaintEvent *event)
                 else
                     r.setRect(pxPosX - _pxCharWidth, pxPosY - _pxCharHeight + _pxSelectionSub, 3*_pxCharWidth, _pxCharHeight);
                 painter.fillRect(r, c);
-                hex = _hexDataShown.mid((bPosLine + colIdx) * 2, 2);
+                hex = _hexDataShown.mid((int)((bPosLine + colIdx) * 2), 2);
 
                 // upper or lower case
                 if (_upperCase)
@@ -887,7 +893,7 @@ void QHexEdit::paintEvent(QPaintEvent *event)
                 // render ascii value
                 if (_asciiArea)
                 {
-                    int ch = (uchar)_dataShown.at(bPosLine + colIdx);
+                    int ch = (uchar)_dataShown.at((int)(bPosLine + colIdx));
                     if ( ch < 0x20 )
                         ch = '.';
                     r.setRect(pxPosAsciiX2, pxPosY - _pxCharHeight + _pxSelectionSub, _pxCharWidth, _pxCharHeight);
@@ -977,12 +983,12 @@ void QHexEdit::setSelection(qint64 pos)
 
 int QHexEdit::getSelectionBegin()
 {
-    return _bSelectionBegin;
+    return (int)_bSelectionBegin;
 }
 
 int QHexEdit::getSelectionEnd()
 {
-    return _bSelectionEnd;
+    return (int)_bSelectionEnd;
 }
 
 // ********************************************************************** Private utility functions
diff --git a/UEFITool/searchdialog.cpp b/UEFITool/searchdialog.cpp
index 74f37b9..a0f74df 100644
--- a/UEFITool/searchdialog.cpp
+++ b/UEFITool/searchdialog.cpp
@@ -16,8 +16,13 @@
 SearchDialog::SearchDialog(QWidget *parent) :
 QDialog(parent, Qt::WindowTitleHint | Qt::WindowSystemMenuHint | Qt::WindowCloseButtonHint),
 ui(new Ui::SearchDialog),
+#if QT_VERSION_MAJOR >= 6
+hexValidator(QRegularExpression("([0-9a-fA-F\\. ])*")),
+guidValidator(QRegularExpression("[0-9a-fA-F\\.]{8}-[0-9a-fA-F\\.]{4}-[0-9a-fA-F\\.]{4}-[0-9a-fA-F\\.]{4}-[0-9a-fA-F\\.]{12}"))
+#else
 hexValidator(QRegExp("([0-9a-fA-F\\. ])*")),
 guidValidator(QRegExp("[0-9a-fA-F\\.]{8}-[0-9a-fA-F\\.]{4}-[0-9a-fA-F\\.]{4}-[0-9a-fA-F\\.]{4}-[0-9a-fA-F\\.]{12}"))
+#endif
 {
     // Create UI
     ui->setupUi(this);
@@ -46,4 +51,4 @@ void SearchDialog::setEditFocus(int index)
     }
     else if (index == 2) // Text
         ui->textEdit->setFocus();
-}
\ No newline at end of file
+}
diff --git a/UEFITool/searchdialog.h b/UEFITool/searchdialog.h
index 56a673c..6698506 100644
--- a/UEFITool/searchdialog.h
+++ b/UEFITool/searchdialog.h
@@ -15,7 +15,13 @@
 #define SEARCHDIALOG_H
 
 #include <QDialog>
+
+#if QT_VERSION_MAJOR >= 6
+#include <QRegularExpressionValidator>
+#else
 #include <QRegExpValidator>
+#endif
+
 #include "ui_searchdialog.h"
 
 class SearchDialog : public QDialog
@@ -31,8 +37,13 @@ private slots:
     void setEditFocus(int index);
 
 private:
+#if QT_VERSION_MAJOR >= 6
+    QRegularExpressionValidator hexValidator;
+    QRegularExpressionValidator guidValidator;
+#else
     QRegExpValidator hexValidator;
     QRegExpValidator guidValidator;
+#endif
 };
 
 #endif // SEARCHDIALOG_H
diff --git a/UEFITool/uefitool.cpp b/UEFITool/uefitool.cpp
index ec22558..0f35f56 100644
--- a/UEFITool/uefitool.cpp
+++ b/UEFITool/uefitool.cpp
@@ -390,7 +390,12 @@ void UEFITool::goToData()
         }
 
         for (int j = i + 1; j < model->rowCount(parent); j++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
             QModelIndex currentIndex = parent.child(j, 0);
+#else
+            QModelIndex currentIndex = parent.model()->index(j, 0, parent);
+#endif
+
             if (model->hasEmptyParsingData(currentIndex))
                 continue;
 
@@ -788,8 +793,14 @@ void UEFITool::showParserMessages()
         return;
 
     std::vector<std::pair<QString, QModelIndex> > messages = ffsParser->getMessages();
+
+#if QT_VERSION_MAJOR < 6
     std::pair<QString, QModelIndex> msg;
+    
     foreach (msg, messages) {
+#else
+    for (const auto &msg : messages) {
+#endif
         QListWidgetItem* item = new QListWidgetItem(msg.first, NULL, 0);
         item->setData(Qt::UserRole, QByteArray((const char*)&msg.second, sizeof(msg.second)));
         ui->parserMessagesListWidget->addItem(item);
@@ -806,8 +817,14 @@ void UEFITool::showFinderMessages()
         return;
 
     std::vector<std::pair<QString, QModelIndex> > messages = ffsFinder->getMessages();
+
+#if QT_VERSION_MAJOR < 6
     std::pair<QString, QModelIndex> msg;
+
     foreach (msg, messages) {
+#else
+    for (const auto &msg : messages) {
+#endif
         QListWidgetItem* item = new QListWidgetItem(msg.first, NULL, 0);
         item->setData(Qt::UserRole, QByteArray((const char*)&msg.second, sizeof(msg.second)));;
         ui->finderMessagesListWidget->addItem(item);
@@ -825,8 +842,14 @@ void UEFITool::showBuilderMessages()
         return;
 
     std::vector<std::pair<QString, QModelIndex> > messages = ffsBuilder->getMessages();
+
+#if QT_VERSION_MAJOR < 6
     std::pair<QString, QModelIndex> msg;
+
     foreach (msg, messages) {
+#else
+    for (const auto &msg : messages) {
+#endif
         QListWidgetItem* item = new QListWidgetItem(msg.first, NULL, 0);
         item->setData(Qt::UserRole, QByteArray((const char*)&msg.second, sizeof(msg.second)));
         ui->builderMessagesListWidget->addItem(item);
diff --git a/UEFITool/uefitool.entitlements b/UEFITool/uefitool.entitlements
new file mode 100644
index 0000000..6b54693
--- /dev/null
+++ b/UEFITool/uefitool.entitlements
@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>com.apple.security.app-sandbox</key>
+	<true/>
+	<key>com.apple.security.assets.movies.read-write</key>
+	<true/>
+	<key>com.apple.security.assets.music.read-write</key>
+	<true/>
+	<key>com.apple.security.assets.pictures.read-write</key>
+	<true/>
+	<key>com.apple.security.files.downloads.read-write</key>
+	<true/>
+	<key>com.apple.security.files.user-selected.read-write</key>
+	<true/>
+	<key>com.apple.security.print</key>
+	<true/>
+</dict>
+</plist>
diff --git a/common/bstrlib/bstrwrap.cpp b/common/bstrlib/bstrwrap.cpp
index e1673fd..1f119ce 100644
--- a/common/bstrlib/bstrwrap.cpp
+++ b/common/bstrlib/bstrwrap.cpp
@@ -697,9 +697,9 @@ int CBString::find (const CBString& b, int pos) const {
 int CBString::find (const char * b, int pos) const {
 int ii, j;
 unsigned char c0;
-register int i, l;
-register unsigned char cx;
-register unsigned char * pdata;
+int i, l;
+unsigned char cx;
+unsigned char * pdata;
 
 	if (NULL == b) {
 #ifdef BSTRLIB_THROWS_EXCEPTIONS
diff --git a/common/ffsbuilder.cpp b/common/ffsbuilder.cpp
index d61fb45..b74e23c 100644
--- a/common/ffsbuilder.cpp
+++ b/common/ffsbuilder.cpp
@@ -90,9 +90,14 @@ USTATUS FfsBuilder::buildCapsule(const UModelIndex & index, UByteArray & capsule
                 msg(usprintf("buildCapsule: building of capsules with %d items is not yet supported", model->rowCount(index)), index);
                 return U_NOT_IMPLEMENTED;
             }
-            
+
             // Build image
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
             UModelIndex imageIndex = index.child(0, 0);
+#else
+            UModelIndex imageIndex = index.model()->index(0, 0, index);
+#endif
+
             UByteArray imageData;
             
             // Check image type
@@ -123,8 +128,8 @@ USTATUS FfsBuilder::buildCapsule(const UModelIndex & index, UByteArray & capsule
             }
             
             // Check size of reconstructed capsule body, it must remain the same
-            UINT32 newSize = capsule.size();
-            UINT32 oldSize = model->body(index).size();
+            UINT32 newSize = (UINT32)capsule.size();
+            UINT32 oldSize = (UINT32)model->body(index).size();
             if (newSize > oldSize) {
                 msg(usprintf("buildCapsule: new capsule size %Xh (%u) is bigger than the original %Xh (%u)", newSize, newSize, oldSize, oldSize), index);
                 return U_INVALID_CAPSULE;
@@ -165,11 +170,19 @@ USTATUS FfsBuilder::buildIntelImage(const UModelIndex & index, UByteArray & inte
     // Rebuild
     else if (model->action(index) == Actions::Rebuild) {
         // First child will always be descriptor for this type of image, and it's read only for now
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         intelImage = model->header(index.child(0, 0)) + model->body(index.child(0, 0)) + model->tail(index.child(0, 0));
-        
+#else
+        intelImage = model->header(index.model()->index(0, 0, index)) + model->body(index.model()->index(0, 0, index)) + model->tail(index.model()->index(0, 0, index));
+#endif
+
         // Process other regions
         for (int i = 1; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
             UModelIndex currentRegion = index.child(i, 0);
+#else
+            UModelIndex currentRegion = index.model()->index(i, 0, index);
+#endif
 
             // Skip regions with Remove action
             if (model->action(currentRegion) == Actions::Remove)
@@ -222,8 +235,8 @@ USTATUS FfsBuilder::buildIntelImage(const UModelIndex & index, UByteArray & inte
         }
         
         // Check size of new image, it must be same as old one
-        UINT32 newSize = intelImage.size();
-        UINT32 oldSize = model->body(index).size();
+        UINT32 newSize = (UINT32)intelImage.size();
+        UINT32 oldSize = (UINT32)model->body(index).size();
         if (newSize > oldSize) {
             msg(usprintf("buildIntelImage: new image size %Xh (%u) is bigger than the original %Xh (%u)", newSize, newSize, oldSize, oldSize), index);
             return U_INVALID_IMAGE;
@@ -269,7 +282,13 @@ USTATUS FfsBuilder::buildRawArea(const UModelIndex & index, UByteArray & rawArea
             // Build children
             for (int i = 0; i < model->rowCount(index); i++) {
                 USTATUS result = U_SUCCESS;
+
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
                 UModelIndex currentChild = index.child(i, 0);
+#else
+                UModelIndex currentChild = index.model()->index(i, 0, index);
+#endif
+
                 UByteArray currentData;
                 // Check child type
                 if (model->type(currentChild) == Types::Volume) {
@@ -292,8 +311,8 @@ USTATUS FfsBuilder::buildRawArea(const UModelIndex & index, UByteArray & rawArea
             }
 
             // Check size of new raw area, it must be same as original one
-            UINT32 newSize = rawArea.size();
-            UINT32 oldSize = model->body(index).size();
+            UINT32 newSize = (UINT32)rawArea.size();
+            UINT32 oldSize = (UINT32)model->body(index).size();
             if (newSize > oldSize) {
                 msg(usprintf("buildRawArea: new area size %Xh (%u) is bigger than the original %Xh (%u)", newSize, newSize, oldSize, oldSize), index);
                 return U_INVALID_RAW_AREA;
diff --git a/common/ffsops.cpp b/common/ffsops.cpp
index 160519e..a2eb09f 100644
--- a/common/ffsops.cpp
+++ b/common/ffsops.cpp
@@ -44,8 +44,13 @@ USTATUS FfsOperations::extract(const UModelIndex & index, UString & name, UByteA
         extracted.clear();
         // There is no need to redo decompression, we can use child items
         for (int i = 0; i < model->rowCount(index); i++) {
-             UModelIndex childIndex = index.child(i, 0);
-             // Ensure 4-byte alignment of current section
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
+            UModelIndex childIndex = index.child(i, 0);
+#else
+            UModelIndex childIndex = index.model()->index(i, 0, index);
+#endif
+            
+            // Ensure 4-byte alignment of current section
              extracted += UByteArray(ALIGN4((UINT32)extracted.size()) - (UINT32)extracted.size(), '\x00');
              // Add current section header, body and tail
              extracted += model->header(childIndex);
diff --git a/common/ffsparser.cpp b/common/ffsparser.cpp
index c4a8ac5..6fd690f 100644
--- a/common/ffsparser.cpp
+++ b/common/ffsparser.cpp
@@ -478,7 +478,7 @@ USTATUS FfsParser::parseIntelImage(const UByteArray & intelImage, const UINT32 l
     // Check for padding after the last region
     if ((UINT64)regions.back().offset + (UINT64)regions.back().length < (UINT64)intelImage.size()) {
         region.offset = regions.back().offset + regions.back().length;
-        region.length = intelImage.size() - region.offset;
+        region.length = (UINT32)(intelImage.size() - region.offset);
         region.data = intelImage.mid(region.offset, region.length);
         region.type = getPaddingType(region.data);
         regions.push_back(region);
@@ -718,10 +718,10 @@ USTATUS FfsParser::parseMeRegion(const UByteArray & me, const UINT32 localOffset
     }
     else {
         // Search for new signature
-        INT32 versionOffset = me.indexOf(ME_VERSION_SIGNATURE2);
+        INT32 versionOffset = (INT32)me.indexOf(ME_VERSION_SIGNATURE2);
         if (versionOffset < 0){ // New signature not found
             // Search for old signature
-            versionOffset = me.indexOf(ME_VERSION_SIGNATURE);
+            versionOffset = (INT32)me.indexOf(ME_VERSION_SIGNATURE);
             if (versionOffset < 0){
                 info += ("\nVersion: unknown");
                 versionFound = false;
@@ -848,7 +848,7 @@ USTATUS FfsParser::parseRawArea(const UModelIndex & index)
 
     // Get item data
     UByteArray data = model->body(index);
-    UINT32 headerSize = model->header(index).size();
+    UINT32 headerSize = (UINT32)model->header(index).size();
 
     USTATUS result;
     UString name;
@@ -919,7 +919,7 @@ USTATUS FfsParser::parseRawArea(const UModelIndex & index)
 
             // Update variables
             prevItemOffset = itemOffset;
-            prevItemSize = padding.size();
+            prevItemSize = (UINT32)padding.size();
             break;
         }
 
@@ -992,7 +992,12 @@ USTATUS FfsParser::parseRawArea(const UModelIndex & index)
 
     // Parse bodies
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         UModelIndex current = index.child(i, 0);
+#else
+        UModelIndex current = index.model()->index(i, 0, index);
+#endif
+
         switch (model->type(current)) {
         case Types::Volume:
             parseVolumeBody(current);
@@ -1122,7 +1127,7 @@ USTATUS FfsParser::parseVolumeHeader(const UByteArray & volume, const UINT32 loc
 
     // Check for AppleCRC32 and UsedSpace in ZeroVector
     bool hasAppleCrc32 = false;
-    UINT32 volumeSize = volume.size();
+    UINT32 volumeSize = (UINT32)volume.size();
     UINT32 appleCrc32 = *(UINT32*)(volume.constData() + 8);
     UINT32 usedSpace = *(UINT32*)(volume.constData() + 12);
     if (appleCrc32 != 0) {
@@ -1295,7 +1300,7 @@ BOOLEAN FfsParser::microcodeHeaderValid(const INTEL_MICROCODE_HEADER* ucodeHeade
 USTATUS FfsParser::findNextRawAreaItem(const UModelIndex & index, const UINT32 localOffset, UINT8 & nextItemType, UINT32 & nextItemOffset, UINT32 & nextItemSize, UINT32 & nextItemAlternativeSize)
 {
     UByteArray data = model->body(index);
-    UINT32 dataSize = data.size();
+    UINT32 dataSize = (UINT32)data.size();
 
     if (dataSize < sizeof(UINT32))
         return U_STORES_NOT_FOUND;
@@ -1435,7 +1440,7 @@ USTATUS FfsParser::parseVolumeBody(const UModelIndex & index)
 
     // Get volume header size and body
     UByteArray volumeBody = model->body(index);
-    UINT32 volumeHeaderSize = model->header(index).size();
+    UINT32 volumeHeaderSize = (UINT32)model->header(index).size();
 
     // Parse VSS NVRAM volumes with a dedicated function
     if (model->subtype(index) == Subtypes::NvramVolume) {
@@ -1466,7 +1471,7 @@ USTATUS FfsParser::parseVolumeBody(const UModelIndex & index)
     }
 
     // Search for and parse all files
-    UINT32 volumeBodySize = volumeBody.size();
+    UINT32 volumeBodySize = (UINT32)volumeBody.size();
     UINT32 fileOffset = 0;
 
     while (fileOffset < volumeBodySize) {
@@ -1496,7 +1501,7 @@ USTATUS FfsParser::parseVolumeBody(const UModelIndex & index)
             if (freeSpace.count(emptyByte) != freeSpace.size()) {
                 // Search for the first non-empty byte
                 UINT32 i;
-                UINT32 size = freeSpace.size();
+                UINT32 size = (UINT32)freeSpace.size();
                 const UINT8* current = (UINT8*)freeSpace.constData();
                 for (i = 0; i < size; i++) {
                     if (*current++ != emptyByte) {
@@ -1559,7 +1564,12 @@ USTATUS FfsParser::parseVolumeBody(const UModelIndex & index)
 
     // Check for duplicate GUIDs
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         UModelIndex current = index.child(i, 0);
+#else
+        UModelIndex current = index.model()->index(i, 0, index);
+#endif
+
         // Skip non-file entries and pad files
         if (model->type(current) != Types::File || model->subtype(current) == EFI_FV_FILETYPE_PAD) {
             continue;
@@ -1570,7 +1580,11 @@ USTATUS FfsParser::parseVolumeBody(const UModelIndex & index)
 
         // Check files after current for having an equal GUID
         for (int j = i + 1; j < model->rowCount(index); j++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
             UModelIndex another = index.child(j, 0);
+#else
+            UModelIndex another = index.model()->index(j, 0, index);
+#endif
 
             // Skip non-file entries
             if (model->type(another) != Types::File) {
@@ -1589,7 +1603,12 @@ USTATUS FfsParser::parseVolumeBody(const UModelIndex & index)
 
     // Parse bodies
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         UModelIndex current = index.child(i, 0);
+#else
+        UModelIndex current = index.model()->index(i, 0, index);
+#endif
+
         switch (model->type(current)) {
         case Types::File:
             parseFileBody(current);
@@ -1704,7 +1723,7 @@ USTATUS FfsParser::parseFileHeader(const UByteArray & file, const UINT32 localOf
     }
 
     // Check header checksum
-    UINT8 calculatedHeader = 0x100 - (calculateSum8((const UINT8*)header.constData(), header.size()) - fileHeader->IntegrityCheck.Checksum.Header - fileHeader->IntegrityCheck.Checksum.File - fileHeader->State);
+    UINT8 calculatedHeader = 0x100 - (calculateSum8((const UINT8*)header.constData(), (UINT32)header.size()) - fileHeader->IntegrityCheck.Checksum.Header - fileHeader->IntegrityCheck.Checksum.File - fileHeader->State);
     bool msgInvalidHeaderChecksum = false;
     if (fileHeader->IntegrityCheck.Checksum.Header != calculatedHeader) {
         msgInvalidHeaderChecksum = true;
@@ -1715,7 +1734,7 @@ USTATUS FfsParser::parseFileHeader(const UByteArray & file, const UINT32 localOf
     bool msgInvalidDataChecksum = false;
     UINT8 calculatedData = 0;
     if (fileHeader->Attributes & FFS_ATTRIB_CHECKSUM) {
-        calculatedData = calculateChecksum8((const UINT8*)body.constData(), body.size());
+        calculatedData = calculateChecksum8((const UINT8*)body.constData(), (UINT32)body.size());
     }
     // Data checksum must be one of predefined values
     else if (volumeRevision == 1) {
@@ -1907,7 +1926,7 @@ USTATUS FfsParser::parsePadFileBody(const UModelIndex & index)
 
     // Search for the first non-empty byte
     UINT32 nonEmptyByteOffset;
-    UINT32 size = body.size();
+    UINT32 size = (UINT32)body.size();
     const UINT8* current = (const UINT8*)body.constData();
     for (nonEmptyByteOffset = 0; nonEmptyByteOffset < size; nonEmptyByteOffset++) {
         if (*current++ != emptyByte)
@@ -1915,7 +1934,7 @@ USTATUS FfsParser::parsePadFileBody(const UModelIndex & index)
     }
 
     // Add all bytes before as free space...
-    UINT32 headerSize = model->header(index).size();
+    UINT32 headerSize = (UINT32)model->header(index).size();
     if (nonEmptyByteOffset >= 8) {
         // Align free space to 8 bytes boundary
         if (nonEmptyByteOffset != ALIGN8(nonEmptyByteOffset))
@@ -1959,8 +1978,8 @@ USTATUS FfsParser::parseSections(const UByteArray & sections, const UModelIndex
         return U_INVALID_PARAMETER;
 
     // Search for and parse all sections
-    UINT32 bodySize = sections.size();
-    UINT32 headerSize = model->header(index).size();
+    UINT32 bodySize = (UINT32)sections.size();
+    UINT32 headerSize = (UINT32)model->header(index).size();
     UINT32 sectionOffset = 0;
     USTATUS result = U_SUCCESS;
 
@@ -2019,7 +2038,12 @@ USTATUS FfsParser::parseSections(const UByteArray & sections, const UModelIndex
 
     // Parse bodies, will be skipped if insertIntoTree is not required
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         UModelIndex current = index.child(i, 0);
+#else
+        UModelIndex current = index.model()->index(i, 0, index);
+#endif
+
         switch (model->type(current)) {
         case Types::Section:
             parseSectionBody(current);
@@ -2278,7 +2302,7 @@ USTATUS FfsParser::parseGuidedSectionHeader(const UByteArray & section, const UI
         UINT32 crc = *(UINT32*)(section.constData() + headerSize);
         additionalInfo += UString("\nChecksum type: CRC32");
         // Calculate CRC32 of section data
-        UINT32 calculated = (UINT32)crc32(0, (const UINT8*)section.constData() + dataOffset, section.size() - dataOffset);
+        UINT32 calculated = (UINT32)crc32(0, (const UINT8*)section.constData() + dataOffset, (uInt)(section.size() - dataOffset));
         if (crc == calculated) {
             additionalInfo += usprintf("\nChecksum: %08Xh, valid", crc);
         }
@@ -2656,7 +2680,7 @@ USTATUS FfsParser::parseCompressedSectionBody(const UModelIndex & index)
 
     // Obtain required information from parsing data
     UINT8 compressionType = EFI_NOT_COMPRESSED;
-    UINT32 uncompressedSize = model->body(index).size();
+    UINT32 uncompressedSize = (UINT32)model->body(index).size();
     if (model->hasEmptyParsingData(index) == false) {
         UByteArray data = model->parsingData(index);
         const COMPRESSED_SECTION_PARSING_DATA* pdata = (const COMPRESSED_SECTION_PARSING_DATA*)data.constData();
@@ -2846,7 +2870,11 @@ USTATUS FfsParser::parseVersionSectionBody(const UModelIndex & index)
         return U_INVALID_PARAMETER;
 
     // Add info
+#if QT_VERSION_MAJOR >= 6
+    model->addInfo(index, UString("\nVersion string: ") + UString::fromUtf16((const char16_t*)model->body(index).constData()));
+#else
     model->addInfo(index, UString("\nVersion string: ") + UString::fromUtf16((const CHAR16*)model->body(index).constData()));
+#endif
 
     return U_SUCCESS;
 }
@@ -2981,7 +3009,11 @@ USTATUS FfsParser::parseUiSectionBody(const UModelIndex & index)
     if (!index.isValid())
         return U_INVALID_PARAMETER;
 
+#if QT_VERSION_MAJOR >= 6
+    UString text = UString::fromUtf16((const char16_t*)model->body(index).constData());
+#else
     UString text = UString::fromUtf16((const CHAR16*)model->body(index).constData());
+#endif
 
     // Add info
     model->addInfo(index, UString("\nText: ") + text);
@@ -2999,7 +3031,7 @@ USTATUS FfsParser::parseAprioriRawSection(const UByteArray & body, UString & par
         msg(usprintf("%s: apriori file has size is not a multiple of 16", __FUNCTION__));
     }
     parsed.clear();
-    UINT32 count = body.size() / sizeof(EFI_GUID);
+    UINT32 count = (UINT32)(body.size() / sizeof(EFI_GUID));
     if (count > 0) {
         for (UINT32 i = 0; i < count; i++) {
             const EFI_GUID* guid = (const EFI_GUID*)body.constData() + i;
@@ -3207,7 +3239,7 @@ USTATUS FfsParser::performSecondPass(const UModelIndex & index)
     }
 
     // Calculate address difference
-    const UINT32 vtfSize = model->header(lastVtf).size() + model->body(lastVtf).size() + model->tail(lastVtf).size();
+    const UINT32 vtfSize = (const UINT32)(model->header(lastVtf).size() + model->body(lastVtf).size() + model->tail(lastVtf).size());
     addressDiff = 0xFFFFFFFFULL - model->base(lastVtf) - vtfSize + 1;
 
     // Parse reset vector data
@@ -3280,7 +3312,7 @@ USTATUS FfsParser::checkTeImageBase(const UModelIndex & index)
         if (originalImageBase != 0 || adjustedImageBase != 0) {
             // Check data memory address to be equal to either OriginalImageBase or AdjustedImageBase
             UINT64 address = addressDiff + model->base(index);
-            UINT32 base = (UINT32)address + model->header(index).size();
+            UINT32 base = (UINT32)(address + model->header(index).size());
 
             if (originalImageBase == base) {
                 imageBaseType = EFI_IMAGE_TE_BASE_ORIGINAL;
@@ -3318,7 +3350,11 @@ USTATUS FfsParser::checkTeImageBase(const UModelIndex & index)
 
     // Process child items
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         checkTeImageBase(index.child(i, 0));
+#else
+        checkTeImageBase(index.model()->index(i, 0, index));
+#endif
     }
 
     return U_SUCCESS;
@@ -3339,7 +3375,7 @@ USTATUS FfsParser::addInfoRecursive(const UModelIndex & index)
         // Add physical address of the whole item or it's header and data portions separately
         UINT64 address = addressDiff + model->base(index);
         if (address <= 0xFFFFFFFFUL) {
-            UINT32 headerSize = model->header(index).size();
+            UINT32 headerSize = (UINT32)model->header(index).size();
             if (headerSize) {
                 model->addInfo(index, usprintf("Data address: %08Xh\n", address + headerSize),false);
                 model->addInfo(index, usprintf("Header address: %08Xh\n", address), false);
@@ -3355,7 +3391,11 @@ USTATUS FfsParser::addInfoRecursive(const UModelIndex & index)
 
     // Process child items
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         addInfoRecursive(index.child(i, 0));
+#else
+        addInfoRecursive(index.model()->index(i, 0, index));
+#endif
     }
 
     return U_SUCCESS;
@@ -3443,7 +3483,7 @@ USTATUS FfsParser::checkProtectedRanges(const UModelIndex & index)
                 else
                 {
                     bgProtectedRanges[i].Offset = model->base(dxeRootVolumeIndex);
-                    bgProtectedRanges[i].Size = model->header(dxeRootVolumeIndex).size() + model->body(dxeRootVolumeIndex).size() + model->tail(dxeRootVolumeIndex).size();
+                    bgProtectedRanges[i].Size = (UINT32)(model->header(dxeRootVolumeIndex).size() + model->body(dxeRootVolumeIndex).size() + model->tail(dxeRootVolumeIndex).size());
                     protectedParts = openedImage.mid(bgProtectedRanges[i].Offset, bgProtectedRanges[i].Size);
 
                     UByteArray digest(SHA256_DIGEST_SIZE, '\x00');
@@ -3534,7 +3574,7 @@ USTATUS FfsParser::markProtectedRangeRecursive(const UModelIndex & index, const
     // Mark normal items
     else {
         UINT32 currentOffset = model->base(index);
-        UINT32 currentSize = model->header(index).size() + model->body(index).size() + model->tail(index).size();
+        UINT32 currentSize = (UINT32)(model->header(index).size() + model->body(index).size() + model->tail(index).size());
 
         if (std::min(currentOffset + currentSize, range.Offset + range.Size) > std::max(currentOffset, range.Offset)) {
             if (range.Offset <= currentOffset && currentOffset + currentSize <= range.Offset + range.Size) { // Mark as fully in range
@@ -3552,7 +3592,11 @@ USTATUS FfsParser::markProtectedRangeRecursive(const UModelIndex & index, const
     }
 
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         markProtectedRangeRecursive(index.child(i, 0), range);
+#else
+        markProtectedRangeRecursive(index.model()->index(i, 0, index), range);
+#endif
     }
 
     return U_SUCCESS;
@@ -3856,7 +3900,12 @@ void FfsParser::findFitRecursive(const UModelIndex & index, UModelIndex & found,
 
     // Process child items
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         findFitRecursive(index.child(i, 0), found, fitOffset);
+#else
+        findFitRecursive(index.model()->index(i, 0, index), found, fitOffset);
+#endif
+
         if (found.isValid())
             return;
     }
@@ -3864,11 +3913,11 @@ void FfsParser::findFitRecursive(const UModelIndex & index, UModelIndex & found,
     // Check for all FIT signatures in item's body
     UByteArray lastVtfBody = model->body(lastVtf);
     UINT32 storedFitAddress = *(const UINT32*)(lastVtfBody.constData() + lastVtfBody.size() - FIT_POINTER_OFFSET);
-    for (INT32 offset = model->body(index).indexOf(FIT_SIGNATURE);
+    for (INT32 offset = (INT32)model->body(index).indexOf(FIT_SIGNATURE);
         offset >= 0;
-        offset = model->body(index).indexOf(FIT_SIGNATURE, offset + 1)) {
+        offset = (INT32)model->body(index).indexOf(FIT_SIGNATURE, offset + 1)) {
         // FIT candidate found, calculate it's physical address
-        UINT32 fitAddress = model->base(index) + (UINT32)addressDiff + model->header(index).size() + (UINT32)offset;
+        UINT32 fitAddress = (UINT32)(model->base(index) + (UINT32)addressDiff + model->header(index).size() + (UINT32)offset);
 
         // Check FIT address to be stored in the last VTF
         if (fitAddress == storedFitAddress) {
@@ -4062,7 +4111,7 @@ USTATUS FfsParser::parseFitEntryBootGuardKeyManifest(const UByteArray & keyManif
 
 USTATUS FfsParser::findNextBootGuardBootPolicyElement(const UByteArray & bootPolicy, const UINT32 elementOffset, UINT32 & nextElementOffset, UINT32 & nextElementSize)
 {
-    UINT32 dataSize = bootPolicy.size();
+    UINT32 dataSize = (UINT32)bootPolicy.size();
     if (dataSize < sizeof(UINT64)) {
         return U_ELEMENTS_NOT_FOUND;
     }
diff --git a/common/ffsreport.cpp b/common/ffsreport.cpp
index 6f06745..8685352 100644
--- a/common/ffsreport.cpp
+++ b/common/ffsreport.cpp
@@ -49,7 +49,7 @@ USTATUS FfsReport::generateRecursive(std::vector<UString> & report, const UModel
     
     // Calculate item CRC32
     UByteArray data = model->header(index) + model->body(index) + model->tail(index);
-    UINT32 crc = (UINT32)crc32(0, (const UINT8*)data.constData(), data.size());
+    UINT32 crc = (UINT32)crc32(0, (const UINT8*)data.constData(), (uInt)data.size());
 
     // Information on current item
     UString text = model->text(index);
@@ -68,7 +68,11 @@ USTATUS FfsReport::generateRecursive(std::vector<UString> & report, const UModel
 
     // Information on child items
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         generateRecursive(report, index.child(i,0), level + 1);
+#else
+        generateRecursive(report, index.model()->index(i,0,index), level + 1);
+#endif
     }
 
     return U_SUCCESS;
diff --git a/common/ffsutils.cpp b/common/ffsutils.cpp
index 45315f2..c9c67a7 100644
--- a/common/ffsutils.cpp
+++ b/common/ffsutils.cpp
@@ -40,7 +40,12 @@ USTATUS findFileRecursive(TreeModel *model, const UModelIndex index, const UStri
 
     bool hasChildren = (model->rowCount(index) > 0);
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         findFileRecursive(model, index.child(i, index.column()), hexPattern, mode, files);
+#else
+        findFileRecursive(model, index.model()->index(i, index.column(), index), hexPattern, mode, files);
+#endif
+
     }
 
     UByteArray data;
diff --git a/common/guiddatabase.cpp b/common/guiddatabase.cpp
index a914821..ee56bc6 100644
--- a/common/guiddatabase.cpp
+++ b/common/guiddatabase.cpp
@@ -116,7 +116,12 @@ GuidDatabase guidDatabaseFromTreeRecursive(TreeModel * model, const UModelIndex
         return db;
 
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         GuidDatabase tmpDb = guidDatabaseFromTreeRecursive(model, index.child(i, index.column()));
+#else
+        GuidDatabase tmpDb = guidDatabaseFromTreeRecursive(model, index.model()->index(i, index.column(), index));
+#endif
+
         db.insert(tmpDb.begin(), tmpDb.end());
     }
 
diff --git a/common/meparser.cpp b/common/meparser.cpp
index 7ce0153..a42de39 100755
--- a/common/meparser.cpp
+++ b/common/meparser.cpp
@@ -165,7 +165,7 @@ USTATUS MeParser::parseFptRegion(const UByteArray & region, const UModelIndex &
 
     // Add partition table entries
     std::vector<FPT_PARTITION_INFO> partitions;
-    UINT32 offset = header.size();
+    UINT32 offset = (UINT32)header.size();
     const FPT_HEADER_ENTRY* firstPtEntry = (const FPT_HEADER_ENTRY*)(region.constData() + offset);
     for (UINT8 i = 0; i < ptHeader->NumEntries; i++) {
         // Populate entry header
@@ -265,7 +265,7 @@ make_partition_table_consistent:
     // Check for padding after the last region
     if ((UINT32)partitions.back().ptEntry.Offset + (UINT32)partitions.back().ptEntry.Size < (UINT32)region.size()) {
         padding.ptEntry.Offset = partitions.back().ptEntry.Offset + partitions.back().ptEntry.Size;
-        padding.ptEntry.Size = region.size() - padding.ptEntry.Offset;
+        padding.ptEntry.Size = (UINT32)(region.size() - padding.ptEntry.Offset);
         padding.type = Types::Padding;
         partitions.push_back(padding);
     }
@@ -422,7 +422,7 @@ make_partition_table_consistent:
     // Check for padding after the last region
     if ((UINT32)partitions.back().ptEntry.Offset + (UINT32)partitions.back().ptEntry.Size < (UINT32)region.size()) {
         padding.ptEntry.Offset = partitions.back().ptEntry.Offset + partitions.back().ptEntry.Size;
-        padding.ptEntry.Size = region.size() - padding.ptEntry.Offset;
+        padding.ptEntry.Size = (UINT32)(region.size() - padding.ptEntry.Offset);
         padding.type = Types::Padding;
         partitions.push_back(padding);
     }
@@ -604,7 +604,7 @@ make_partition_table_consistent:
     // Check for padding after the last region
     if ((UINT32)partitions.back().ptEntry.Offset + (UINT32)partitions.back().ptEntry.Size < (UINT32)region.size()) {
         padding.ptEntry.Offset = partitions.back().ptEntry.Offset + partitions.back().ptEntry.Size;
-        padding.ptEntry.Size = region.size() - padding.ptEntry.Offset;
+        padding.ptEntry.Size = (UINT32)(region.size() - padding.ptEntry.Offset);
         padding.type = Types::Padding;
         partitions.push_back(padding);
     }
diff --git a/common/nvramparser.cpp b/common/nvramparser.cpp
index 7fd684e..275b790 100755
--- a/common/nvramparser.cpp
+++ b/common/nvramparser.cpp
@@ -45,7 +45,7 @@ USTATUS NvramParser::parseNvarStore(const UModelIndex & index)
     }
 
     // Get local offset
-    UINT32 localOffset = model->header(index).size();
+    UINT32 localOffset = (UINT32)model->header(index).size();
 
     // Get item data
     const UByteArray data = model->body(index);
@@ -121,7 +121,7 @@ USTATUS NvramParser::parseNvarStore(const UModelIndex & index)
                 guidArea.size(), guidArea.size(),
                 guidsInStore);
             // Add tree item
-            model->addItem(localOffset + offset + padding.size(), Types::Padding, getPaddingType(guidArea), name, UString(), info, UByteArray(), guidArea, UByteArray(), Fixed, index);
+            model->addItem((UINT32)(localOffset + offset + padding.size()), Types::Padding, getPaddingType(guidArea), name, UString(), info, UByteArray(), guidArea, UByteArray(), Fixed, index);
 
             return U_SUCCESS;
         }
@@ -230,7 +230,12 @@ USTATUS NvramParser::parseNvarStore(const UModelIndex & index)
             // Search previously added entries for a link to this variable
             // WARNING: O(n^2), may be very slow
             for (int i = model->rowCount(index) - 1; i >= 0; i--) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
                 nvarIndex = index.child(i, 0);
+#else
+                nvarIndex = index.model()->index(i, 0, index);
+#endif
+
                 if (model->hasEmptyParsingData(nvarIndex) == false) {
                     UByteArray nvarData = model->parsingData(nvarIndex);
                     const NVAR_ENTRY_PARSING_DATA nvarPdata = readUnaligned((const NVAR_ENTRY_PARSING_DATA*)nvarData.constData());
@@ -261,11 +266,16 @@ USTATUS NvramParser::parseNvarStore(const UModelIndex & index)
             UINT32 nameSize = 0;
             if (entryHeader->Attributes & NVRAM_NVAR_ENTRY_ASCII_NAME) { // Name is stored as ASCII string of CHAR8s
                 text = UString(namePtr);
-                nameSize = text.length() + 1;
+                nameSize = (UINT32)(text.length() + 1);
             }
             else { // Name is stored as UCS2 string of CHAR16s
+#if QT_VERSION_MAJOR >= 6
+                text = UString::fromUtf16((char16_t*)namePtr);
+#else
                 text = UString::fromUtf16((CHAR16*)namePtr);
-                nameSize = (text.length() + 1) * 2;
+#endif
+
+                nameSize = (UINT32)((text.length() + 1) * 2);
             }
 
             // Get entry GUID
@@ -388,7 +398,7 @@ USTATUS NvramParser::parseNvramVolumeBody(const UModelIndex & index)
     }
 
     // Get local offset
-    UINT32 localOffset = model->header(index).size();
+    UINT32 localOffset = (UINT32)model->header(index).size();
 
     // Get item data
     UByteArray data = model->body(index);
@@ -455,7 +465,7 @@ USTATUS NvramParser::parseNvramVolumeBody(const UModelIndex & index)
 
             // Update variables
             prevStoreOffset = storeOffset;
-            prevStoreSize = padding.size();
+            prevStoreSize = (UINT32)padding.size();
             break;
         }
 
@@ -497,7 +507,12 @@ USTATUS NvramParser::parseNvramVolumeBody(const UModelIndex & index)
 
     // Parse bodies
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         UModelIndex current = index.child(i, 0);
+#else
+        UModelIndex current = index.model()->index(i, 0, index);
+#endif
+
         switch (model->type(current)) {
         case Types::FdcStore:
             parseFdcStoreBody(current);
@@ -528,7 +543,7 @@ USTATUS NvramParser::parseNvramVolumeBody(const UModelIndex & index)
 
 USTATUS NvramParser::findNextStore(const UModelIndex & index, const UByteArray & volume, const UINT32 localOffset, const UINT32 storeOffset, UINT32 & nextStoreOffset)
 {
-    UINT32 dataSize = volume.size();
+    UINT32 dataSize = (UINT32)volume.size();
 
     if (dataSize < sizeof(UINT32))
         return U_STORES_NOT_FOUND;
@@ -1286,7 +1301,7 @@ USTATUS NvramParser::parseFdcStoreBody(const UModelIndex & index)
     const UByteArray data = model->body(index);
 
     // Get local offset
-    UINT32 localOffset = model->header(index).size();
+    UINT32 localOffset = (UINT32)model->header(index).size();
 
     // The body is a firmware volume with either a VSS or VSS2 store
     UModelIndex volumeIndex;
@@ -1300,14 +1315,14 @@ USTATUS NvramParser::parseFdcStoreBody(const UModelIndex & index)
     UByteArray store = model->body(volumeIndex);
     if ((UINT32)store.size() >= sizeof(UINT32) && *(const UINT32*)store.constData() == NVRAM_VSS_STORE_SIGNATURE) {
         UModelIndex vssIndex;
-        status = parseVssStoreHeader(store, localOffset + model->header(volumeIndex).size(), true, volumeIndex, vssIndex);
+        status = parseVssStoreHeader(store, (UINT32)(localOffset + model->header(volumeIndex).size()), true, volumeIndex, vssIndex);
         if (status)
             return status;
         return parseVssStoreBody(vssIndex, 0);
     }
     else if ((UINT32)store.size() >= sizeof(EFI_GUID) && store.left(sizeof(EFI_GUID)) == NVRAM_FDC_STORE_GUID) {
         UModelIndex vss2Index;
-        status = parseVss2StoreHeader(store, localOffset + model->header(volumeIndex).size(), true, volumeIndex, vss2Index);
+        status = parseVss2StoreHeader(store, (UINT32)(localOffset + model->header(volumeIndex).size()), true, volumeIndex, vss2Index);
         if (status)
             return status;
         return parseVssStoreBody(vss2Index, 0);
@@ -1335,7 +1350,7 @@ USTATUS NvramParser::parseVssStoreBody(const UModelIndex & index, UINT8 alignmen
     }
 
     // Get local offset
-    UINT32 localOffset = model->header(index).size();
+    UINT32 localOffset = (UINT32)model->header(index).size();
 
     // Get item data
     const UByteArray data = model->body(index);
@@ -1396,7 +1411,7 @@ USTATUS NvramParser::parseVssStoreBody(const UModelIndex & index, UINT8 alignmen
 
                     // Calculate CRC32 of the variable data
                     storedCrc32 = appleVariableHeader->DataCrc32;
-                    calculatedCrc32 = (UINT32)crc32(0, (const UINT8*)body.constData(), body.size());
+                    calculatedCrc32 = (UINT32)crc32(0, (const UINT8*)body.constData(), (uInt)body.size());
                 }
             }
 
@@ -1501,7 +1516,12 @@ USTATUS NvramParser::parseVssStoreBody(const UModelIndex & index, UINT8 alignmen
         else { // Add GUID and text for valid variables
             name = guidToUString(readUnaligned(variableGuid));
             info += UString("Variable GUID: ") + guidToUString(readUnaligned(variableGuid), false) + UString("\n");
+
+#if QT_VERSION_MAJOR >= 6
+            text = UString::fromUtf16((char16_t *)variableName);
+#else
             text = UString::fromUtf16(variableName);
+#endif
         }
 
         // Add info
@@ -1555,7 +1575,7 @@ USTATUS NvramParser::parseFsysStoreBody(const UModelIndex & index)
         return U_INVALID_PARAMETER;
 
     // Get local offset
-    UINT32 localOffset = model->header(index).size();
+    UINT32 localOffset = (UINT32)model->header(index).size();
 
     // Get item data
     const UByteArray data = model->body(index);
@@ -1658,7 +1678,7 @@ USTATUS NvramParser::parseEvsaStoreBody(const UModelIndex & index)
     }
 
     // Get local offset
-    UINT32 localOffset = model->header(index).size();
+    UINT32 localOffset = (UINT32)model->header(index).size();
 
     // Get item data
     const UByteArray data = model->body(index);
@@ -1732,7 +1752,13 @@ USTATUS NvramParser::parseEvsaStoreBody(const UModelIndex & index)
             const EVSA_NAME_ENTRY* nameHeader = (const EVSA_NAME_ENTRY*)entryHeader;
             header = data.mid(offset, sizeof(EVSA_NAME_ENTRY));
             body = data.mid(offset + sizeof(EVSA_NAME_ENTRY), nameHeader->Header.Size - sizeof(EVSA_NAME_ENTRY));
+
+#if QT_VERSION_MAJOR >= 6
+            name = UString::fromUtf16((const char16_t *)body.constData());
+#else
             name = UString::fromUtf16((const CHAR16*)body.constData());
+#endif
+
             info = UString("Name: ") + name + usprintf("\nFull size: %Xh (%u)\nHeader size %Xh (%u)\nBody size: %Xh (%u)\nType: %02Xh\nChecksum: %02Xh",
                 variableSize, variableSize,
                 header.size(), header.size(),
@@ -1805,7 +1831,12 @@ USTATUS NvramParser::parseEvsaStoreBody(const UModelIndex & index)
 
     // Reparse all data variables to detect invalid ones and assign name and test to valid ones
     for (int i = 0; i < model->rowCount(index); i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         UModelIndex current = index.child(i, 0);
+#else
+        UModelIndex current = index.model()->index(i, 0, index);
+#endif
+
         if (model->subtype(current) == Subtypes::DataEvsaEntry) {
             UByteArray header = model->header(current);
             const EVSA_DATA_ENTRY* dataHeader = (const EVSA_DATA_ENTRY*)header.constData();
@@ -1857,7 +1888,7 @@ USTATUS NvramParser::parseFlashMapBody(const UModelIndex & index)
         return U_INVALID_PARAMETER;
 
     // Get parsing data for the current item
-    UINT32 localOffset = model->header(index).size();
+    UINT32 localOffset = (UINT32)model->header(index).size();
     const UByteArray data = model->body(index);
 
 
diff --git a/common/sha256.c b/common/sha256.c
index 9177f45..cd269b1 100644
--- a/common/sha256.c
+++ b/common/sha256.c
@@ -109,8 +109,8 @@ static void sha256_compress(struct sha256_state *md, unsigned char *buf)
     }
     /* Compress */
 #define RND(a,b,c,d,e,f,g,h,i)                          \
-t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i];	\
-t1 = Sigma0(a) + Maj(a, b, c);			\
+t0 = (uint32_t)(h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i]);	\
+t1 = (uint32_t)(Sigma0(a) + Maj(a, b, c));			\
 d += t0;					\
 h  = t0 + t1;
     for (i = 0; i < 64; ++i) {
diff --git a/common/treemodel.cpp b/common/treemodel.cpp
index 60b29b1..99b0442 100644
--- a/common/treemodel.cpp
+++ b/common/treemodel.cpp
@@ -43,7 +43,7 @@ QVariant TreeModel::data(const UModelIndex &index, int role) const
 Qt::ItemFlags TreeModel::flags(const UModelIndex &index) const
 {
     if (!index.isValid())
-        return 0;
+        return Qt::NoItemFlags;
 
     return Qt::ItemIsEnabled | Qt::ItemIsSelectable;
 }
@@ -559,9 +559,14 @@ UModelIndex TreeModel::findByBase(UINT32 base) const
 goDeeper:
     int n = rowCount(parentIndex);
     for (int i = 0; i < n; i++) {
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
         UModelIndex currentIndex = parentIndex.child(i, 0);
+#else
+        UModelIndex currentIndex = parentIndex.model()->index(i, 0, parentIndex);
+#endif
+    
         UINT32 currentBase = this->base(currentIndex);
-        UINT32 fullSize = header(currentIndex).size() + body(currentIndex).size() + tail(currentIndex).size();
+        UINT32 fullSize = (UINT32)(header(currentIndex).size() + body(currentIndex).size() + tail(currentIndex).size());
         if ((compressed(currentIndex) == false || (compressed(currentIndex) == true && compressed(currentIndex.parent()) == false)) // Base is meaningful only for true uncompressed items
             && currentBase <= base && base < currentBase + fullSize) { // Base must be in range [currentBase, currentBase + fullSize)
             // Found a better candidate
diff --git a/common/treemodel.h b/common/treemodel.h
index b1ef19e..5e90dd9 100644
--- a/common/treemodel.h
+++ b/common/treemodel.h
@@ -86,7 +86,6 @@ private:
 #if defined(QT_CORE_LIB)
 class TreeModel : public QAbstractItemModel
 {
-    Q_OBJECT
 private:
     TreeItem *rootItem;
     bool markingEnabledFlag;
diff --git a/common/ubytearray.h b/common/ubytearray.h
index 6cf2710..143b850 100644
--- a/common/ubytearray.h
+++ b/common/ubytearray.h
@@ -45,14 +45,14 @@ public:
     UByteArray toUpper() { std::basic_string<char> s = d; std::transform(s.begin(), s.end(), s.begin(), ::toupper); return UByteArray(s); }
     uint32_t toUInt(bool* ok = NULL, const uint8_t base = 10) { return (uint32_t)strtoul(d.c_str(), NULL, base); }
 
-    int32_t size() const { return d.size();  }
-    int32_t count(char ch) const { return std::count(d.begin(), d.end(), ch); }
+    int32_t size() const { return (int32_t)d.size();  }
+    int32_t count(char ch) const { return (int32_t)std::count(d.begin(), d.end(), ch); }
     char at(uint32_t i) const { return d.at(i); }
     char operator[](uint32_t i) const { return d[i]; }
     char& operator[](uint32_t i) { return d[i]; }
 
     bool startsWith(const UByteArray & ba) const { return 0 == d.find(ba.d, 0); }
-    int indexOf(const UByteArray & ba, int from = 0) const { return d.find(ba.d, from); }
+    int indexOf(const UByteArray & ba, int from = 0) const { return (int)d.find(ba.d, from); }
     int lastIndexOf(const UByteArray & ba, int from = 0) const {
         size_t old_index = d.npos;
         size_t index = d.find(ba.d, from);
@@ -60,7 +60,7 @@ public:
             old_index = index;
             index = d.find(ba.d, index + 1);
         }
-        return old_index;
+        return (int)old_index;
     }
 
     UByteArray left(int32_t len) const { return d.substr(0, len); }
diff --git a/common/ustring.cpp b/common/ustring.cpp
index 89cfe36..d9d7bd4 100644
--- a/common/ustring.cpp
+++ b/common/ustring.cpp
@@ -19,7 +19,13 @@ UString usprintf(const char* fmt, ...)
     UString msg;
     va_list vl;
     va_start(vl, fmt);
+
+#if ((QT_VERSION_MAJOR == 5) && (QT_VERSION_MINOR < 6)) || (QT_VERSION_MAJOR < 5)
     msg.vsprintf(fmt, vl);
+#else
+    msg = msg.vasprintf(fmt, vl);
+#endif
+
     va_end(vl);
     return msg;
 };
diff --git a/common/utility.cpp b/common/utility.cpp
index 3e9f418..0cfd203 100755
--- a/common/utility.cpp
+++ b/common/utility.cpp
@@ -102,7 +102,7 @@ UString uniqueItemName(const UModelIndex & index)
         '<', '>', ':', '\"', '\\', '|', '?', '*', // Banned in Windows
         ' ' // Provides better readability
     };
-    int nameLength = name.length(); // Note: Qt uses int for whatever reason.
+    int nameLength = (int)name.length(); // Note: Qt uses int for whatever reason.
     for (int i = 0; i < nameLength; i++) {
         for (size_t j = 0; j < sizeof(table); j++) {
             if (name[i] == table[j]) {
@@ -200,7 +200,7 @@ USTATUS decompress(const UByteArray & compressedData, const UINT8 compressionTyp
 
         // Get buffer sizes
         data = (UINT8*)compressedData.data();
-        dataSize = compressedData.size();
+        dataSize = (UINT32)compressedData.size();
 
         // Check header to be valid
         header = (const EFI_TIANO_HEADER*)data;
@@ -260,7 +260,7 @@ USTATUS decompress(const UByteArray & compressedData, const UINT8 compressionTyp
 
         // Get buffer sizes
         data = (const UINT8*)compressedData.constData();
-        dataSize = compressedData.size();
+        dataSize = (UINT32)compressedData.size();
 
         // Get info as normal LZMA section
         if (U_SUCCESS != LzmaGetInfo(data, dataSize, &decompressedSize)) {
@@ -305,7 +305,7 @@ USTATUS decompress(const UByteArray & compressedData, const UINT8 compressionTyp
 
         // Get buffer sizes
         data = (const UINT8*)compressedData.constData();
-        dataSize = compressedData.size();
+        dataSize = (UINT32)compressedData.size();
 
         // Get info as normal LZMA section
         if (U_SUCCESS != LzmaGetInfo(data, dataSize, &decompressedSize)) {
@@ -498,7 +498,7 @@ USTATUS gzipDecompress(const UByteArray & input, UByteArray & output)
 
     z_stream stream;
     stream.next_in = (z_const Bytef *)input.data();
-    stream.avail_in = input.size();
+    stream.avail_in = (uInt)input.size();
     stream.zalloc = Z_NULL;
     stream.zfree = Z_NULL;
     stream.opaque = Z_NULL;
diff --git a/version.h b/version.h
index 0b43aa8..711b3c4 100644
--- a/version.h
+++ b/version.h
@@ -14,6 +14,6 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #ifndef VERSION_H
 #define VERSION_H
 
-#define PROGRAM_VERSION "NE alpha 58" " (" __DATE__ ")"
+#define PROGRAM_VERSION "NE alpha 59" " (" __DATE__ ")"
 
 #endif // VERSION_H