hey,
I installed it and it on my Win7-64-bit system and it worked on the same day. Today when I tried to create a PDF an error message popped saying that there is no printer. The PDF-Creater-printer was gone. So I uninstalled and reinstalled PDF-C and now the printer is there but when I print something it just doesn´t do anything.
The print job is visible in the printer properties but that´s it, no PDF is created. The print job is stuck. :(
I have a similar problem after updating to 1.2.2, also on W7 64 bit. It seems to work OK from the user interface, but not using automation. I tried to go back to 1.2.1, but that also doesn't seem to be working, either :-(
I fixed it (for now) by installing the optional .NET Framework 4 patches KB2533523 and KB2468871.
The reason I thought that it could help was that there was a security update for .net 4 so I thought maybe that update was messing with pdf-creator.
Although I have to test if it still works after I restart my PC again.
Or maybe just deinstalling PDF-C and restarting the PC fixed it and the patches where totally useless… I guess I´ll never know 
One weird thing happend when I installed it the last time. Before I did I checked the printers and no printer was there. During installation I got an errormessage saying that a printer named PDF-Creator was already there. I checked and it was there so I renamed the printer to pdf-creator2.
After the installation was finished I checked the printers again and now only the printer pdf-creator2 was there again. No sight of the printer with the name “pdf-creator”. Pretty weird somehow.
My printer service was deactivated (since I had no printer before). After setting the service to auto the printer reappeared.