I'm having a strange problem. I just recently installed Kdenlive. The first project I did with it went fine. I had to apt-get install some codec packages and run the configuration wizard but everything went off without a hitch.

Now on my second project for some reason when I render, regardless of which choice I made, rendering completes instantly and generates a 0kb file. There are no visible warnings or errors displayed by the program. How can I diagnose this and fix it?

Aha! Found the problem upon further googling. Please see https://bugs.kdenlive.org/view.php?id=2592 if you are having this issue.