Not to rain on your parade, but this sounds like a huge waste of time. Spend a half an hour getting rsync working which was made for this sort of task. If you can manage to write this program you describe setting up rsync should be trivial. Leave the rsync server running as a service on your PC and add a hijack menu_exec option to initiate the rsync from the empeg. Then you don't need to build a GUI and all you have to do is select rsync from the empeg and off you go.

-Mike