I have a project that is a composite of silent video tracks & mp3 and video that contains it's own sound.

It previews just fine.

When it goes to render pitivi disappears. No error is given, it just goes away. At first I thought the process died, I would just start up another pitivi and try again. Same problem. Then I checked (ps ax | grep pitivi) and saw that pitivi was still running!

I've tried it repeatedly for this same project with always the same result. Sometimes pitivi is still running, just not displayed (and I kill it), and sometimes it's not.

One really handy tool would be something that can convert the xptv files into mencoder instructions. I'd be happy to whip that up if someone will provide the documentation to the internals - I've looked through it and need a rough explanation of how those huge ints are calculated for the start and duration offsets.