Which Windows Operating Systems (32-bit and 64-bit) can PDFCreator 1.2.1 be installed on?

Help!!!!  It is 2AM and I have been searching for a couple of hours trying to find System Requirements for PDFCreator 1.2.1 with no luck.

Are there Windows OS differences (both 32-bit & 64-bit versions) for the stand alone PDFCreator printer and the print server based PDFCreator printer?

I am interested in the both 32-bit & 64-bit versions of WinXP, Win7, WinServer2003, WinServer2008.

Thanks for any help that anyone can give me!