After installation of Parallels Tools on Parallels 11 Win 10 ... VM just hangs

[Parallels User]

I've read a bunch of threads here, but haven't seen exactly this problem and though someone might have an idea.

First ... I successfully upgraded to Win 10 (still on Parallels 10) and ran it for several weeks with no major issues.

1. Just bought and installed Parallels 11 (the Pro version).
2. Everything went smoothly and used the Win 10 VM just fine for a few days.
3. Today, it popped up and said it needed to install Parallel Tools and proceeded to do so.
4. Parallel Tools installed successfully and then it needed a RESTART
5. Win 10 shut down fine and then starts to restart.
6. Ends up just hanging in the boot screen (see attached JPG)
7. Activity Monitor shows Windows 10 (my VM) using 100+ CPU and it's been running for a long time but nothing happens
8. I see ReportCrash show up in Activity Monitor ... run for a bit, go away, then come back ... kind of leading me to believe something is in a loop of crashing or something?
9. After fiddling for a LONG time, I can rollback a few snapshots to before the Parallels Tools installs and get Win 10 to come up successfully (and it immediately wants to install Parallel Tools again).

SO... at least from what I'm seeing something with the installation of the Parallels Tools is wonky on my VM? Or? Help!