I'm using Vista x64 and have the latest CCCP, AviSynth 2.5.7 and CoreAVC 1.9.5 installed. Even though I enabled AviSynth/FFmpeg in the PMS configuration and bumped it to the top of the priority list, it does not seem to work. In the Transcode directory on my 360 there is no AviSynth/FFmpeg selection, only Mencoder and AviSynth/Mencoder. I can confirm that CoreAVC works since I regularly watch h264 files on my PC and disabled ffdshow from decoding h264 content. Mencoder takes up about 60% of processing power when streaming to my 360 so I would like to utilize CoreAVC and its CUDA acceleration.