I've had a bit of a play and had at least some partial success.
The winxp pro sp3 install saw the new hardware, I installed the drivers. Yet the devices wouldn't show up in the device list.
Do you mean the tv tuner card didn't show up in Windows Device Manager, or in didn't show up in MP TVServer?
Sorry for late reply. (Didn't get email about new posts)...
The Tv tuner didn't show up in the windows device manager, although the drivers looked like they installed ok. They didn't show any error's.
I've removed the ESXi setup for now, but would like to try again latter.. Hopefully you get some good results. It could also be with the mb I'm using, as I didn't want to go i5/7 for this test. I had the cpu here already, and just got the mb.