Hi northasaurus,
We have seen this a couple of times before and right now there is the work around of saving your image again and once in awhile making your image a little smaller. Our development team is working on why and when this happens, as it does not happen to everyone. Please contact me directly if you are still having problems with your images.
Sincerely,
Owen
NetBlender DoStudio Blu-ray Team - DSA -
http://dostudio.netblender.com