VPUML unstable in saving

I have tried to work with VPUML fro a week. After I lost my model first time (one day of work) I started to save from time to time and commit in CVS every new save.
Today, again the same problem.
I have saved a couple of snapshots. VPUML repory as saved, though the files where truncated at almost half size and could not be reloaded (not even as a part of model). I was not inspired to check every time if the files are growing in size so I lost another day of work. Does anyone experience the same problem when the model grows?
This is not acceptable…

Hi Victor,
Could you use the feed back to send us the log file. The feed back feature can be found in pull down menu Tools->Feedback.

Best Regards,
Angus