^^^

Holy crap!!! That seems to have done it!! For three days I've been trying to solve this and figure it out, and tried every idea and suggestion available without success, until now! Disabling those three options now allows P4 to run just as it did under my old system, with no highlighting problems of any kind!

THANK YOU!! And thank you very much to everyone who offered their kind assistance here in this thread and the other one. I truly appreciate it and am grateful for every suggestion and the time taken to help.

I'll update the other thread with this solution...