diff --git a/basetypes.h b/basetypes.h
index b564fc7..9bd594e 100644
--- a/basetypes.h
+++ b/basetypes.h
@@ -82,6 +82,7 @@ typedef uint16_t  CHAR16;
 #define ERR_GENERIC_CALL_NOT_SUPPORTED      32
 #define ERR_VOLUME_BASE_NOT_FOUND           33
 #define ERR_PEI_CORE_ENTRY_POINT_NOT_FOUND  34
+#define ERR_COMPLEX_BLOCK_MAP               35
 #define ERR_NOT_IMPLEMENTED                 0xFF
 
 // Compression algorithms
diff --git a/ffsengine.cpp b/ffsengine.cpp
index 179ff82..27e7f54 100644
--- a/ffsengine.cpp
+++ b/ffsengine.cpp
@@ -40,7 +40,7 @@ TreeModel* FfsEngine::treeModel() const
     return model;
 }
 
-void FfsEngine::msg(const QString & message, const QModelIndex index)
+void FfsEngine::msg(const QString & message, const QModelIndex & index)
 {
     messageItems.enqueue(MessageListItem(message, NULL, 0, index));
 }
@@ -1848,7 +1848,7 @@ UINT8 FfsEngine::compress(const QByteArray & data, const UINT8 algorithm, QByteA
 }
 
 // Construction routines
-UINT8 FfsEngine::constructPadFile(const QByteArray guid, const UINT32 size, const UINT8 revision, const UINT8 erasePolarity, QByteArray & pad)
+UINT8 FfsEngine::constructPadFile(const QByteArray &guid, const UINT32 size, const UINT8 revision, const UINT8 erasePolarity, QByteArray & pad)
 {
     if (size < sizeof(EFI_FFS_FILE_HEADER) || erasePolarity == ERASE_POLARITY_UNKNOWN)
         return ERR_INVALID_PARAMETER;
@@ -2690,8 +2690,7 @@ UINT8 FfsEngine::growVolume(QByteArray & header, const UINT32 size, UINT32 & new
     EFI_FV_BLOCK_MAP_ENTRY* blockMap = (EFI_FV_BLOCK_MAP_ENTRY*) (header.data() + sizeof(EFI_FIRMWARE_VOLUME_HEADER));
 
     // Get block map size
-    UINT32 extHeaderOffset = volumeHeader->Revision == 2 ? volumeHeader->ExtHeaderOffset : 0;
-    UINT32 blockMapSize = header.size() - extHeaderOffset - sizeof(EFI_FIRMWARE_VOLUME_HEADER);
+    UINT32 blockMapSize = volumeHeader->HeaderLength - sizeof(EFI_FIRMWARE_VOLUME_HEADER);
     if (blockMapSize % sizeof(EFI_FV_BLOCK_MAP_ENTRY))
         return ERR_INVALID_VOLUME;
     UINT32 blockMapCount = blockMapSize / sizeof(EFI_FV_BLOCK_MAP_ENTRY);
@@ -2700,13 +2699,19 @@ UINT8 FfsEngine::growVolume(QByteArray & header, const UINT32 size, UINT32 & new
     if (blockMap[blockMapCount-1].NumBlocks != 0 || blockMap[blockMapCount-1].Length != 0)
         return ERR_INVALID_VOLUME;
 
+    // Case of complex blockMap
+    //!TODO: implement this case
+    if (blockMapCount > 2)
+        return ERR_COMPLEX_BLOCK_MAP;
+
     // Calculate new size
     if (newSize <= size)
         return ERR_INVALID_PARAMETER;
-    newSize += blockMap->Length - newSize % blockMap->Length;
+    
+    newSize += blockMap[0].Length - newSize % blockMap[0].Length;
 
     // Recalculate number of blocks
-    blockMap->NumBlocks = newSize / blockMap->Length;
+    blockMap[0].NumBlocks = newSize / blockMap[0].Length;
 
     // Set new volume size
     volumeHeader->FvLength = 0;
diff --git a/ffsengine.h b/ffsengine.h
index 92a3ba3..4113efd 100644
--- a/ffsengine.h
+++ b/ffsengine.h
@@ -98,7 +98,7 @@ private:
     UINT8 getSectionSize(const QByteArray & file, const UINT32 sectionOffset, UINT32 & sectionSize);
 
     // Reconstruction helpers
-    UINT8 constructPadFile(const QByteArray guid, const UINT32 size, const UINT8 revision, const UINT8 erasePolarity, QByteArray & pad);
+    UINT8 constructPadFile(const QByteArray &guid, const UINT32 size, const UINT8 revision, const UINT8 erasePolarity, QByteArray & pad);
     UINT8 growVolume(QByteArray & header, const UINT32 size, UINT32 & newSize);
 
     // Rebase routines
@@ -112,7 +112,7 @@ private:
 
     // Message helper
     QQueue<MessageListItem> messageItems;
-    void msg(const QString & message, const QModelIndex index = QModelIndex());
+    void msg(const QString & message, const QModelIndex &index = QModelIndex());
 
     // Internal operations
     bool hasIntersection(const UINT32 begin1, const UINT32 end1, const UINT32 begin2, const UINT32 end2);
diff --git a/uefitool.ui b/uefitool.ui
index d671e82..ff86839 100644
--- a/uefitool.ui
+++ b/uefitool.ui
@@ -20,7 +20,7 @@
    <bool>true</bool>
   </property>
   <property name="windowTitle">
-   <string>UEFITool 0.17.6</string>
+   <string>UEFITool 0.17.7</string>
   </property>
   <widget class="QWidget" name="centralWidget">
    <property name="sizePolicy">