Did you ever solve the problem with getting the custom dictionary to "stick" in Word and if so how?
No, I didn't solve that one and I was busy so I left it alone after a few tries. There are two Custom Dictionaries and one will stick but the second won't.
The normal fix for icon display problems is using OnyX or a similar utility to rebuild the "Launch Services" database. Your oddly mixed results leads me to suspect possible underlying permission issues as well, but I would start with the LaunchServices Database rebuild.
I'll give that a try (have never used Onyx) but I wonder if I should first confirm that I still have 11.6.2, by reinstalling it.
ryck