PADS Standard and Standard Plus run in 32-bit mode on 64-bit PCs.
Pads Professional is only available in a 32 bit version at this time, but stay tuned for announcements on future releases.
The 32 bit version runs great on 64 bit Windows OS, so there is no problems.
As for 64 bit solutions, there is sometimes a misunderstanding that they run faster. Typically, they run about the same speed. This is true of our 64 bit Xpedition products. What 64 bit will give you though, is the ability to address much larger design databases, as the memory will be allowed to better address their size.
Stay tuned for more information in the future!