They now both install fine!!
No issues with XR settings, except the fact that the quest is missing some settings, but it's not the apps problem since your app is just the launcher.
Same can be said for the file manager, it starts on portrait and doesn't like to be resized, ends up in a blank or white screen. I'm guessing that's an older Android file manager limitation.
I haven't tried the optimiser, but if you send me a time limit licence or similar, I'd be happy to try it and report back to you.
Cheers