Yeah, thatâ€™s probably it. DVD Shrink just uses Neroâ€™s burning API, so try setting the option in Nero, then see if it sticks in Shrink.
Iâ€™m sure itâ€™s a registry entry that determines that behavior, but since I donâ€™t use Nero, I canâ€™tâ€¦ nevermind, I just did a quick search. Try this if youâ€™re familiar with registry mods:
[HKEY_CURRENT_USER\SOFTWARE\Ahead\Nero - Burning Rom\General]