just an update on Windows Security & PIN setup issue - after a few weeks of searching my system I, for no real reason, clicked to open credential mgr. and it didnt open. I checked and the service was stopped, and further inspection (properties) showed startup was somehow disabled. Changed to automatic and restarted service and voila! I was able to setup my Windows Hello PIN and that pesky little red X over windows security icon (system tray and in settings) was gone and I was able to now access all of the apps that required authentication with my PIN that wouldn't work since the diagnostic mode disaster.
If you followed the steps listed and were successful wonderful, but if you now have any issues with Win. Security or Hello PIN take a look if credential mgr is running.