If you can create a capture graph in GraphEdit then I could try adding support for it to WinTvCap30.
I'm not sure if I would be able to control any of the audio/video capture settings since they're in a "secret" interface on all the other analog capture devices and I'm not sure it exists the same way on the HD-PVR
If someone wants to send me one, I have a vcr that outputs HD component. I could try it.
K.