I've been getting this error for quite some time, can someone please tell me how to MAKE it compatible?
This will help you. Read the first post. There are some required things that need to be on a map before you can use a certain gametype with it. Bungie.net : Halo: Reach Forum : Forge Required Objects Guide
That's stupid right?! 95% of the maps that I downloaded and played in custom games said the same thing for me. Why would people take the time to make a racetrack and not make it compatible? It's stupid IMO.