I was working on a project for 5 hours today. Occasionally I would get the "yellow triangle" corruption, which I would fix by closing WLMM and reopening it. I save every couple of minutes so no biggie. However, after working on my project for 5 hours, it happened, probably for the 3rd time in that session, and when I reopened it, everything on my timeline was GONE. It's bizarre, it behaves as if it's still there. Under the preview window it says "0:00:00 / 3:07:23" and if I press "play" the little mark will move along as if everything was there. But there is no video or audio. On the right I can even scroll up and down this great nothingness. I tried loading the "autosave.wlmp" with the same results.

I'm running on Windows 8.1, I have the latest version of WLMM and all of my drivers are updated. Every file I had imported into WLMM was an mp4 or mp3.