So I'm going to wait and see what happens once the creators update goes properly live via WU to all non-insiders..

It feels like a permissions issue to me of some kind, but I can't see anything obvious in the procmon output to suggest what is actually going on.
If I have time next week, I'm going to compare it to the working Win10Pro VM that I have that is still on 1607 (build 14393.1066)