After solving the interference of a driver with my BD authoring through Express Burn, I attempted to export my good sequence to ISO for BDMV from within V-Pad. Took about 3 hours. After creating an ISO, it seems like V-Pad halts there without an obvious route to write it. Writing it using Express Burn, where it was easy, the burn was a no-go for a play test. Coaster again!
My impression is that V-Pad is best only for getting you to a video data output file, and that E/B should take over from there if you want a valid burn in blu-ray. My subsequent trial with E/B creating an ISO, and handling the BD burn, with the exact same file that V-Pad failed with, and all was well. I'd love an explanation......