Just in case this helps anyone else ...
I was working on a project that was almost 2hrs long. I successfully finished the project, added menus, and was ready to encode, but Pre8 kept crashing on me during the encoding. I thought it was end markers (since there's been a lot of discussion about them), but end markers are only a problem when they are placed at the end of the project, since a movie will return to the menu anyway at the end of the video. I checked for outdated drivers, my drives were all defragged - still no help. I even was getting the blue screen of death periodically during the encoding process.
Well I discovered a comment that gaps in the timeline can cause issues, so I removed the gaps I had and - Problem Solved!!
So, I think I'll use longer fade-outs, or the dip-to-black transition for my gaps from now on.
I'm posting my challenges, in case it helps anyone else.
You are so correct that gaps can create issues, especially with DVD Projects. The DVD-specs. are based on Video, and authoring programs want to see a 100% contiguous Video Track. If necessary, one can insert synthetic Video, like Black Video, or even Transparent Video, to "fill the gaps." In most cases, just adjusting either the In & Out Points, of butting up the Clips is the answer.
Often, the Sonic AuthorCore modules (used in both PrE, and Encore - plus older versions of PrPro) will throw an error message along the lines of "failure to return frame," or similar. Other times, things just crash, with zero error messages.
Thanks for reporting,
PS - I had one Project that I inherited. Over 4 DVD's, it had over 900 gaps. The previous editor had burned DVD's for that client, so obviously, the gaps did NOT crash the Project. Still, first thing that I did was remove all the gaps. In my case, these were between about 3000 stills, so it was fairly easy to just adjust the In, or Out Points on the stills, usually by 1 - 2 Frames. Still, 900+ gaps did not cause problems, but I have seen a 1 Frame gap kill a Project, until it was removed. Why? Wish I knew what was different in that case.