I discovered another sync fix. FTM stores temporary files that are used while the sync is in progress. If the connection times out these can become corrupt.

Do this when FTM is not running on Windows. From the C: level of My Computer, look under Documents and Setting, find the user you are logged in as, Local Settings, Temp

Delete the FTM folder.

Start FTM and try to resync.

You may have to resolve minor differences if any.