Zion, the biggest problem I've had with the splicing in Womble is the mismatch in volume between the French/Spanish tracks and the English 5.1 track. Going from 5.1 to 2.0 isn't desired either, hence why this is becoming more complicated. I did this nicely in the stereo track by just replacing the entire ending at the point of the funeral pyre onward with the french language track. Since there is no dialogue, there was no need to return to the English and make yet one more edit. It worked great for the English 2.0 track, once I was able to crossfade the two stereo tracks (again, the volume is not at the same level on the two files.
Now I need (a) to find or (b) to generate a 5.1 track (sans Gungan dialect) for splicing into the original English 5.1, and then (c) figure out how to crossfade it if I can't get the volume to match at the splice point.
Once again, BeSweet is ticking me off, as it won't actually output any WAVs for me (this program never outputs a doggone thing for me). I did try what you suggested ... break the AC3 out into six waves and edit in a multi-track editor like Sonar, which I use in my studio. From there I'd need to figure out how to recombine and recompress into AC3.
Vegas and Combustion are now on the back burner for licensing reasons. I'm an old pro at SoundForge XP so I know I'll like Vegas if I get into it seriously.