Unlike Addon 1 and 2, which automatically launched the Setup program when I popped in the CD, TrueScale required me to open Windows Explorer or My Computer, display the list of files, and run the Setup program manually. I have helped a couple of friends to install AFPD, recently, so it is fresh in my mind.

I would just Right Click on Start, Left Click on Explore, find the TrueScale CD, Left Click on it, Right Click on Setup, and Left Click on Open. If you cannot see the contents of the CD, take it out of the CD/DVD player, check to see that it is clean, put it back in the tray and try again to read it. If it fails to read, try another data CD just to see if the Reader is OK. Try the TrueScale CD in another computer just to see if you can read the files.