I've had this before, I think it's fairly common. For the missing keys, run the terminal for the nextcloud container in the Docker page (not the general unraid terminal option on the top right corner) and type 'occ db:add-missing-primary-keys' which should sort that. For the phone region, there's a great video here to edit your config file:
I'm not sure on the others, I think the X-Frame-Options can be solved in your reverse proxy config - but don't quote me on that one, I may be remembering that one wrong.
xxDeadbolt's post in Nextcloud set up warnings. was marked as the answer