OmegaMattman said:

Next was to create the channels for my 5.1 file. In Vegas, I used the VST effect program V.I. Stereo to 5.1 Converter. If you decide to use it, you can read its manual to figure out how best to do this for you. The important thing is to end up with 6 separate Mono PCM Wav files at 16bits and 48kHz: Front Left, Front Right, Surround Left, Surround Right, Center, and LFE.

It's probably not the most efficient solution. But, when I was in a panic trying to fix this mess, it was the best I could come up with.

Interesting. I wonder if that VST was around when I made my own 2.0 to 5.1 conversion. It would have been a lot easier to split up the channels in Vegas. I wonder, though...why didn't you also use Vegas to make the subsequent AC3?