According to the system requirements listed on the application's official webpage, Autodesk Process Analysis works on 64-bit systems as well as on 32-bit ones. However, Windows 7, seems to be the only compatible operating system.
Furthermore, according to an announcement made by the company, Autodesk Process Analysis will be retired on July 13th, 2017 and you will no longer be able to use the tool past that date. (The files that you've created with it will still be usable though, but you'll need a newer tool to open them.)
