I have a new core i7 920 w/9 Gig ram running Vegas 8.1 64-bit on Vista 64-bit OS. No firewall or online access. Whether I am editing mpg footage or AVCHD mts files, I get a red screen on the video track of the timeline, and a black picture. Audio plays fine. I can't get the AVCHD to render, so I loaded video from a back-up DVD of the event. Vegas imported DVD files to mpg. Sometimes I can open an mpg file, sometimes it says there is an error with the file. I change settings to various things, but no luck. First time using the 64 bit 8.1 program with HD. Any ideas?