I've updated my system to Windows 7 64 bit and had to reinstall all of my software, Pksharpener included. There does not appear to be a 64 bit version. The FAQ mentions a Beta for Windows Vista, but that was years ago and they have not updated the release program in years. I tried to install into win32 and on attempting to activate, I received the message that it had been activated too many times. After some research I saw that one could contact PixelGenius support to have the install counter reset and did so via the provided e-mail link but have received no response.
I now do my capture sharpening in ACR, but find the output sharpening in that program awkward to use and have been using PK for that purpose, since I don't use Lightroom. Time to look for another option?