Voxmagna:

You must be comfortable with Regedit Registry editing.

This raises the hurdle up to my nostrils.   Not impossible, and no criminal penalties for failure, but high enough to prefer a workaround--or a patch.

Does the 4.7 GB DVD-SL ceiling persist when one starts a brand new project?  Or, with a new project, can one select a larger destination disk and burn a >5 GB project without getting the "disk full" message?

I imagine the problem could be worst when burning several discs from disk images, some of them under 4.7GB and others larger.  Does it do any good at all to exit the program or restart the PC between a burn of a DVD-SL and a burn of a larger project to a DVD-DL or a BD?  Once an existing project is burnt to a SL disc, is it impossible to burn an HD one to a DL or BD disc without the Regedit Registy editing you prescribe?  How about if one copies the timeline from one project to the virgin timeline of a new one, then burn AVCHD to DL or BD?