It has been years since I used AutoRealm but I downloaded it again and took a quick look.

If you go to Transform -> Position -> Bring Grid Forward (Ctrl+Alt+F) it will move the grid above the first thing you placed, and then the next one, and so on. So if you press it a lot of times it'll bring it to the very top. I don't know if there is a way to group objects so you can do it all in one go though so you might need to press it many times on an existing map.