Thanks. No rush. I fired up one of my win7 pro 64bit machines where vhs to dvd3 is installed, plugged in the interface, and as an experiment, ran the Roxio update. Worked fine there.... but of course, the win7 machine doesn't need a win10 compatibility update.
Rather than uninstalling vhs to dvd from the win10 machine, I'll just wipe the drive and restore an image of the fresh install from a few days ago pre-Roxio. As I'm in the midst of building ou the win10 configuration and testing programs as I go, it's faster for me to go back to step 1 with the win install. So far, all my win7 programs work great on win10 tests... even some of my ancient win98se based midi programs are just fine. vhs to dvd3 was the first glitch. Although like I say, maybe I don't even need the win10 patch... the program and interface seem to be working fine without the update... on first tests anyway.
I did the original cd install using default locations. In fact the locations match on my win10 and win7 computers when I take a look at where the folders are. Don't know why the update can't find things.... such is life with computers.