Just to recap. . .I finally uninstalled everything related to P3D and FSX. I did not save any portions of it to "stick" back in after the new installation. All scenery, airplanes, gauges, effects, sounds were scraped. All controller settings, scenery cfg's, dll's, xml's. . .everything gone. I ran CCleaner several times then did searches manually through the Registry several times. . .leaving nothing to chance. I then defraged and optimized the two drives that had housed the FSX and P3D programs and finally rebooted.
I installed P3D_V3.4.22.19868 in it's entirety on a different drive than it's previous installation. I flew a short flight, shut it down and defraged/reboot. I added one freeware/native FSX aircraft and flew a short flight, Ops chk OK, deactivated that one and replaced it with another. . .short flight, Ops chk ok, and so on. If I had a problem with an airplane it was deleted (no matter if it was a favorite or not). . .tired of constant lock ups and fatal errors.
For scenery, I installed only Orbx Basic, Global Vector and Global LC. I have regions and individual airports but those are not installed yet, no big hurry to do that as I rarely use them. I then selected 5 airports of mine from the Long Island sound area and installed them. I ran each airport through ADE one more time to ensure there were no faults (orphan nodes, links, parking spots "will" cause problems). Once everything checked I flew that area and had no problems during an hour and thirty minute flight.
Finally I installed FSUIPC (registered version). FSX Installation and testing has followed the same process and thus far I have had no problems.