Had the day off yesterday and had a time to mess with it a bit more. It had an update to ver 1.5.1, without warning, just shut down and updated. Easy to tell when it's not working once you have things where you want them. I'm pleased to find that the added headroom that FSR gives, makes it possible to super sample much higher than I usually would.
I tried the old Flyinside Fight Sim X mod and had the same issue as I originally did with the new MS fight Sim, mouse restricted to where I couldn't click on "Fly Now" I was able to launch it OK with the shortcut F key.
I also got it to work on the new MS flight sim and finally got to try my first training session since I bought the game last November. Using the shortcut ctrl+alt+s and timing seems to be the key.
Most of my tinkering has been done with the G2, but I also tried it with Quest 2 and link cable with Aircar, since Aircar has SS other advanced graphics settings. Just as with the G2 and Steam games, I was able to push Aircar far beyond anything I was able too without FSR, and seen it like I've never seen it before on an Oculus HMD.
Not just something I'm going to use only on the few games that the G2 struggles with at 100% res. Big game changer here.
Edit to add: Star Wars Squadrons greatly improved with FSR and the G2 at default res with room to grow.