Using Version 1.3.1 on a German XP SP3 "PDFCreator.exe" stays loaded after succesful printing but no GUI is viewable, just in the task manager. Thus an re-opening of PDFCreator.exe by double klicking it's shortcut on the desktop (for setting of options, etc.) is not possible.
After killing PDFCreator.exe one can open it againg and it has a GUI again.
But after Printing it's the same.