Thanks for the file, Scott.
Very nice of you to use Google, and for the effort to put this together.
I can reproduce it with your file as well, and it is the version that has this problem.
Workaround.
Interactive Mapping is a comfortable way to do it. Besides that, it can be done manually.
Personally, I prefer it manually anyway, and the only extra step you have to do is to select all polygons that should be affected, then assign it to the UV tag. (No clicking on Start/Stop Interactive Mapping needed!)
Be careful if you have more UV tags on the specific object. A Material tag (UVW mapping selected) always uses the UVW map directly to its right in the Object Manager
Screen-capture and project file:
https://www.amazon.com/clouddrive/share/XNKh0ZjMMnwhppZ7wzuEopurUc520flJrEXOqhFZ7bH
I hope that helps until the fix for the problem is available.
All the best