That doesn't seem likely - I could usually do 3-4 burns under Linux before the settings reverted, and I always used the same burning command (growisofs -speed 4 -Z /dev/dvd=dvd.iso). I would think that if growisofs were responsible that the settings would be cancelled immediately. It was all using the same spool of media as well. But perhaps some other application using the drive was responsible, like maybe ripping audio CD's through Sound Juicer? Does the Lite-On firmware have any kind of generic "reset to factory default" command that might be triggered somewhere?
Hmm... I haven't explored Build mode yet. I had stumbled onto a guide to using pgcedit for that and was trying to follow it, but couldn't get it working properly (possibly due to running under WINE). Maybe I'll check out how ImgBurn handles it. In any event, the discs burned with growisofs built from genisoimage mostly seem to handle the split just fine, though I did have one disc that hung my standalone player on the split. I thought that might just have to do with burning at the speed limit of the media, and haven't seen the problem since. But maybe I'll play around some more with ImgBurn and see how that works.
I don't know if the calculation is done also when you try to burn an ISO file.
From the wording of the error message ImgBurn popped up, it sounds like the location of the layer split is coded into the IFO's inside the ISO. So I don't know if ImgBurn would adjust this if you're feeding it an already-mastered ISO. But then growisofs seems to manage this somehow, so who knows?
As always with optical storage, I'm amazed at how much complexity there is under the hood. Most other OS and application functions are really much simpler than they initially appear. But optical storage always seems like just the opposite.