I posted recently about trying to shut off short lead-out and not being able to. I investigated further after removing and re-installing Nero which did ultimate fix the problem. Anyway, I was able to reproduce it by unchecking "high compatibility mode (at least 1 gig written)" for a given burner. If you do that then Nero 126.96.36.199 will start writing short lead-outs even though you have the generate short lead-out box unchecked in the preferences. The only way to shut it off at this point is to re-enable "dvd high compatibility mode" for the recorder.
Why do I uncheck high compatibility mode? I'm creating Xbox backups the retain the original file layout structure as the original without any padding. Some of the layouts are under 1 gig.
I'm using Alcohol to burn my .ISO images under 1 gig until this bug is corrected.