iDVD 3.0.1 for me will freeze at the end of a multi-hour burn without
burning anything, forever claiming it would finish in a minute.
I would need to "Force quit",
then I would find a clean unwritten DVD in the drive.
I first suspected a hardware problem, but no, the finder could burn a DVD.
As the movie was large and debugging took multiple days,
I can only report on my suspicions. My prime suspicion
is the "Brush Strokes" theme with chapters.
I found even the previewer failed.
It would not properly return to the opening page.
Then I tried ...