I was working on a DL project in DVDA3. Opened and closed, saved etc. the project several times as it took a day or so to complete. I prepared the project for burning. The rendering took 8hrs. Then finally burned it to DVD DL today. Now when I go to open the project to make changes I get an error that says "DVD.dar is not a valid project". I can't open the project. Has anyone run across this? I need help. Thanks.