Might as well put this out there.
If you have a valid kickstart 1.3 and 3.1 imported. Then adding games, you can select A500 and A1200. It will use the correct kickstart.
If kickstarts are not present, it will fallback to AROS rom.
So if you select A500, it will boot like a normal A500 with Kickstart 1.3.
I'm saying this, as in a video I saw yesterday, user was saying Rainbow Islands doesnt work. It does, we were using it to test configs.