Hello everyone, I've been lurking the site for a while and finally decided to sign up just to post this. After a little bit of tinkering (and reading the remote control manual) I have figured out how to get the PCTV Series remote to work with Windows Media Center as well as Pinnacle TVCenter Pro.
Download the modified profile and paste it into "C:\ProgramData\Pinnacle\Remoterm\Profiles" if your using Vista, (sorry don't know the folder for XP) be sure to back up the original, but just in case here's my orignial.
Here is the reference diagram I made to show the functions of buttons: (sorry the NumPad had to be sacrificed)

Click the image to download a much larger version of the diagram. Enjoy people!