Thanks for sticking with the process as long as you have. Regarding your points; In point 1, the first six words up to your bold 'only' reflects my experience with Artist Performance Files. I've used Artist Performance Files since 2014-15 era and never experienced the issues from all of point one after the bold only - through the entirety of points 2 and 3. I can't speculate to why you get results different from mine. I don't believe it's buggy for no other reason that as much as I use the feature, I would have run into the same errors you have and I haven't. My demonstrations prepared for you were all quick and easy one take renders no different than all other times I've done it in the past. Musocity's copy/paste method also works and I believe a better option than exporting to a DAW.

BIAB 2025:RB 2025, Latest builds: Dell Optiplex 7040 Desktop; Windows-10-64 bit, Intel Core i7-6700 3.4GHz CPU and 16 GB Ram Memory.