Are there any known compatibility problems between DVD Workshop SE and other programs?

Since 2 days (before that it worked fine) my Ulead DVD Workshop SE (or DVD PowerTools SE however you may call it - the SE version is a cheaper, older, limited edition) freezes when I choose the menu "create disc" (so the window does not appear). Unfortunatly, it's almost impossible to find out what caused the problem, because since I tried to something out, I've installed many different programs (PGCEdit, MenuEdit, DVDAuthor among others) and I guess one of them has overwritten files which DVD Workshop used...
I already uninstalled all these programs, and reinstalled DVD Workshop but nothing helped. And I don't want to reinstall my whole PC...

Anyone got some ideas?