I think you are always better off doing an Advanced Burn and build the disc to your hard drive then burn with toast….you don’t have to burn an IMG file, but the actual VideoTS and AudioTS files in Toast. Using this workflow you will be able to easily make more copies if you need them.
One thing to try, if you insist on burning out of DVDSP is to try trashing the compressor prefs and maybe the Finder Prefs.
Rich Rubasch
Tilt Media