Index: src/libchcore/TLocalFilesystem.cpp
===================================================================
diff -u -r3c343f2e7aa0d489706136e78f2f56cdd5d417a9 -rb75259a9158d8b46d747e20ab4960dd002adb4b1
--- src/libchcore/TLocalFilesystem.cpp	(.../TLocalFilesystem.cpp)	(revision 3c343f2e7aa0d489706136e78f2f56cdd5d417a9)
+++ src/libchcore/TLocalFilesystem.cpp	(.../TLocalFilesystem.cpp)	(revision b75259a9158d8b46d747e20ab4960dd002adb4b1)
@@ -40,6 +40,7 @@
 #include "TFileTime.h"
 #include "TOverlappedDataBuffer.h"
 #include "RoundingFunctions.h"
+#include <atltrace.h>
 
 BEGIN_CHCORE_NAMESPACE
 
@@ -458,7 +459,8 @@
 	if (!IsOpen())
 		THROW_CORE_EXCEPTION(eErr_InternalProblem);
 
-	if (!::ReadFileEx(m_hFile, rBuffer.GetBufferPtr(), rBuffer.GetRequestedDataSize(), &rBuffer, OverlappedReadCompleted))
+	ATLTRACE(_T("Reading %lu bytes\n"), rBuffer.GetRequestedDataSize());
+	if(!::ReadFileEx(m_hFile, rBuffer.GetBufferPtr(), rBuffer.GetRequestedDataSize(), &rBuffer, OverlappedReadCompleted))
 	{
 		DWORD dwLastError = GetLastError();
 		switch(dwLastError)
@@ -494,6 +496,7 @@
 	if (m_bNoBuffering && rBuffer.IsLastPart())
 		dwToWrite = RoundUp<DWORD>(dwToWrite, MaxSectorSize);
 
+	ATLTRACE(_T("Writing %lu bytes\n"), dwToWrite);
 	if (!::WriteFileEx(m_hFile, rBuffer.GetBufferPtr(), dwToWrite, &rBuffer, OverlappedWriteCompleted))
 	{
 		if (GetLastError() == ERROR_IO_PENDING)
@@ -511,9 +514,11 @@
 
 	if (m_bNoBuffering && rBuffer.IsLastPart())
 	{
-		DWORD dwToWrite = boost::numeric_cast<DWORD>(rBuffer.GetBytesTransferred());
+		DWORD dwToWrite = boost::numeric_cast<DWORD>(rBuffer.GetRealDataSize());
 		DWORD dwReallyWritten = RoundUp<DWORD>(dwToWrite, MaxSectorSize);
 
+		ATLTRACE(_T("Finalize file - size diff: written: %I64u, required: %I64u\n"), dwReallyWritten, dwToWrite);
+
 		if (dwToWrite != dwReallyWritten)
 		{
 			unsigned long long ullNewFileSize = rBuffer.GetFilePosition() + dwToWrite;	// new size
@@ -522,6 +527,7 @@
 				return false;
 
 			//seek
+			ATLTRACE(_T("Truncating file to %I64u bytes\n"), ullNewFileSize);
 			if (!SetFilePointer(ullNewFileSize, FILE_BEGIN))
 				return false;
 
Index: src/libchcore/TOverlappedDataBuffer.cpp
===================================================================
diff -u -r3c343f2e7aa0d489706136e78f2f56cdd5d417a9 -rb75259a9158d8b46d747e20ab4960dd002adb4b1
--- src/libchcore/TOverlappedDataBuffer.cpp	(.../TOverlappedDataBuffer.cpp)	(revision 3c343f2e7aa0d489706136e78f2f56cdd5d417a9)
+++ src/libchcore/TOverlappedDataBuffer.cpp	(.../TOverlappedDataBuffer.cpp)	(revision b75259a9158d8b46d747e20ab4960dd002adb4b1)
@@ -35,9 +35,10 @@
 
 ///////////////////////////////////////////////////////////////////////////////////
 // class TOverlappedDataBuffer
-VOID CALLBACK OverlappedReadCompleted(DWORD dwErrorCode, DWORD /*dwNumberOfBytesTransfered*/, LPOVERLAPPED lpOverlapped)
+VOID CALLBACK OverlappedReadCompleted(DWORD dwErrorCode, DWORD dwNumberOfBytesTransfered, LPOVERLAPPED lpOverlapped)
 {
 	TOverlappedDataBuffer* pBuffer = (TOverlappedDataBuffer*) lpOverlapped;
+	ATLTRACE(_T("OverlappedReadCompleted - read %I64u bytes\n"), pBuffer->GetBytesTransferred());
 
 	bool bEof = (dwErrorCode == ERROR_HANDLE_EOF ||
 		pBuffer->GetStatusCode() == STATUS_END_OF_FILE ||
@@ -50,14 +51,16 @@
 	if (dwErrorCode != ERROR_SUCCESS)
 		ATLTRACE(_T("OverlappedReadCompleted error: %lu, status code: %I64u\n"), dwErrorCode, pBuffer->GetStatusCode());
 
+	pBuffer->SetRealDataSize(dwNumberOfBytesTransfered);
 	pBuffer->SetLastPart(bEof);
 	pBuffer->RequeueAsFull();
 }
 
 VOID CALLBACK OverlappedWriteCompleted(DWORD dwErrorCode, DWORD /*dwNumberOfBytesTransfered*/, LPOVERLAPPED lpOverlapped)
 {
 	TOverlappedDataBuffer* pBuffer = (TOverlappedDataBuffer*) lpOverlapped;
-	if (dwErrorCode != ERROR_SUCCESS)
+	ATLTRACE(_T("OverlappedWriteCompleted - written %I64u bytes\n"), pBuffer->GetBytesTransferred());
+	if(dwErrorCode != ERROR_SUCCESS)
 		ATLTRACE(_T("OverlappedWriteCompleted error: %lu, status code: %I64u\n"), dwErrorCode, pBuffer->GetStatusCode());
 
 	pBuffer->RequeueAsFinished();
@@ -68,7 +71,8 @@
 	m_stBufferSize(0),
 	m_bLastPart(false),
 	m_pQueue(pQueue),
-	m_dwRequestedDataSize(0)
+	m_dwRequestedDataSize(0),
+	m_dwRealDataSize(0)
 {
 	if (!m_pQueue)
 		THROW_CORE_EXCEPTION(eErr_InvalidPointer);
Index: src/libchcore/TOverlappedDataBuffer.h
===================================================================
diff -u -r3c343f2e7aa0d489706136e78f2f56cdd5d417a9 -rb75259a9158d8b46d747e20ab4960dd002adb4b1
--- src/libchcore/TOverlappedDataBuffer.h	(.../TOverlappedDataBuffer.h)	(revision 3c343f2e7aa0d489706136e78f2f56cdd5d417a9)
+++ src/libchcore/TOverlappedDataBuffer.h	(.../TOverlappedDataBuffer.h)	(revision b75259a9158d8b46d747e20ab4960dd002adb4b1)
@@ -72,6 +72,9 @@
 	void SetBytesTransferred(ULONG_PTR ulBytes) { InternalHigh = ulBytes; }
 	ULONG_PTR GetBytesTransferred() const { return InternalHigh; }
 
+	DWORD GetRealDataSize() const { return m_dwRealDataSize; }
+	void SetRealDataSize(DWORD dwRealDataSize) { m_dwRealDataSize = dwRealDataSize; }
+
 	unsigned long long GetFilePosition() const { return (unsigned long long)OffsetHigh << 32 | Offset; }
 	void SetFilePosition(unsigned long long ullPosition) { OffsetHigh = (DWORD) (ullPosition >> 32); Offset = (DWORD) ullPosition; }
 
@@ -85,7 +88,7 @@
 	LPVOID m_pBuffer;				// pointer to the allocated buffer
 	size_t m_stBufferSize;			// total buffer size
 	DWORD m_dwRequestedDataSize;	// part of the buffer that is to be used for data transfer (<= m_stBufferSize)
-
+	DWORD m_dwRealDataSize;			// data size as reported by read operation
 	DWORD m_dwErrorCode;			// win32 error code
 	bool m_bLastPart;				// marks the last part of the file
 	unsigned long long m_ullBufferOrder;	// marks the order of this buffer
Index: src/libchcore/TSubTaskCopyMove.cpp
===================================================================
diff -u -r3c343f2e7aa0d489706136e78f2f56cdd5d417a9 -rb75259a9158d8b46d747e20ab4960dd002adb4b1
--- src/libchcore/TSubTaskCopyMove.cpp	(.../TSubTaskCopyMove.cpp)	(revision 3c343f2e7aa0d489706136e78f2f56cdd5d417a9)
+++ src/libchcore/TSubTaskCopyMove.cpp	(.../TSubTaskCopyMove.cpp)	(revision b75259a9158d8b46d747e20ab4960dd002adb4b1)
@@ -295,6 +295,8 @@
 	AdjustBufferIfNeeded(pData->dbBuffer, pData->tBufferSizes);
 	pData->dbBuffer.DataSourceChanged();
 
+	ATLTRACE(_T("CustomCopyFile: %s\n"), pData->spSrcFile->GetFullFilePath().ToString());
+
 	// establish count of data to read
 	TBufferSizes::EBufferType eBufferIndex = GetBufferIndex(pData->tBufferSizes, pData->spSrcFile);
 	m_tSubTaskStats.SetCurrentBufferIndex(eBufferIndex);