I am converting my home miniDV tapes to DVD. For each tape I have one hour of digital video that I clean up in Premier Pro and then export as .avi file. I then import this .avi file into Encore DVD 1.5, create a simple menu that gives you access to the single timeline and then burn to DVD. To maintain a similar look to my DVDs (menu, text, etc) I
Recreating the AVI file probably won't help. Just for the sake of a test, try putting the AVI into a new Encore project and try to build it from there. Don't worry about fancy menus or chapter points or anything. Just something simple for a test. If that works, your existing project has probably corrupted.
If it doesn't work, Encore is probably having some sort of issue with the AVI file. Try choosing a specific transcode setting rather than automatic, and see if that gets around the problem.