i just had the same problem. changed the "decoder option" to VMR Renderer" within the software. then while in device manager, Sound Video and Game Controllers" I tried updating the driver for the "FusionHDTV DVB-T AVS Video Capture". pointed it to the vista drivers that i had downloaded and after installing the drivers it asked for and scanned for TV chanels. I could see a TV picture (no sound) and windows shut the TV application down. I re-booted and launched the fusion software. got an access error. launched the TV and the "FusionHDTV Application has stopped working" and windows shut it down. I also got a message that media centre closed and that the bug would be fixed in the final release, how comforting!
so to be clear, i installed the 3.41 app (all 50.1Mb). when it asked for drivers i said NO. latter on in device manager i updated the driver with the vista drivers and i momentarily got a picture.
Cheers
Robert
all this on Vista build 5386 on a P1.6Ghz with 768Mg ram with a gigabyte 6200 Video card. I am surprised to see aero is working.