I've just discovered, I have the same problem - syncing only few folders from `My Documents` on XP with same folders but in `Documents` on 7. Last week, when I run disk defrag on my XP and I've noticed it takes long time to defrag sync.log - the file size was 4GB! I've stopped sync, moved file to different folder and restarted sync, after a week the file was huge again! This problem is not happening on my 7. Would it have anything to do with endless sync loop of locked files? Sometimes when I open file in some program, the file gets some exclusive lock - the BTSync stalls on syncing with this specific file. After I close the program, BTSync still shows this file in sync queue, forever.
