I just picked up kdenlive (which I've used once or twice for little projects) and assembled an HD video with a new audio track, one sound effect, 2 cuts, and some fades. I had crashes during render when I was on a bad mix of libavcodec versions, but going to http://ppa.launchpad.net/sunab/kdenlive-release/ubuntu fixed it. I think the audio fadeout didn't work in the render, but it worked during interactive playback.

Nice work, everyone who's contributed!