Occasionally when you're trying to burn a dual-layer DVD using Toast 9 Titanium you might encounter some rather cryptic errors (along the lines of "lost communication with drive" and such) if you're running Leopard as your OS. If you encounter these errors, one workaround we've found is to build your Toast session as you normally would, but instead of burning the disc, create a disc image (the "Save as a Disc Image" button is in the lower right-hand corner of the Toast window). Then open a new session, set it up to burn a dual-layer DVD using the disc image as your source material rather than dragging the individual files or folders into the Toast window and it should burn trouble-free.