Thank you for the comment, I now have realized that the true cause of my problem will be too complicated to figure out. Just a bit of advice to MCE installers, I made this installation CD with driverpacks integrated into the installer to try and make things more simple, but when I reinstalled with the standard MCE installer CDs, there wasn't any capture card problem. I wish I could find more information and help the driverpacks people, but that client's PC is long gone now!
Thank you for your consideration.