I have updated PDFCreator to version 0.9.8 on Vista (with many problems that I solved finally by adding option /ForceInstall).
I used the standard installation, and I try print a document from Word, on the "PDFCreator" printer. My document is correctly printed and it is displayed by PDFReader, but just after the window in which I can choose the name of the document appears anew. And it never stops, whatever I do ! When I try to delete the document from the queue, it reappears immediatly. So the only way to stop it was to close the queue manager (I'm not sure, I tried so many things...). And after I can't print another document because the queue manager is stopped.
I think that Vista had virtualized the registry when I had the previous version of PDF Creator which was not totally compatible with Vista, so the virtualized keys were standing on the machine even after uninstallation. This explain all the problems I encountered to install the new version (the necessity of using /ForceInstall option). And after I don't no exactly what was the wrong key which caused my prints to repeat, but it is solved, so it is the most important !