User made maps are used in the SEA and the Combat Theater. Here are several things to notice when making them:
1) Test the map for ex. in H2H with your friends: There cannot be any bugs or errors. TE's "Object Report" don't tell all the errors from the map. You must test and test it
2) Use the HTC default fields or look from them what stuff must be in the airfields and VH bases. Use the default "Field cap" town (2-3 miles away from field), it is standard.
3) CT and SEA maps are historical maps and there must be only two sides in the map. They are very often Bishops (Allies) and Knights (Axis).
4) You must create to Rooks the HQ and 2-3 airfields (only tower and maproom). Place them for ex. outside of the clipboard map area to a little isle. Map is not working if you don't have them somewhere.
5) Best CT maps scales are normally 1:1 - 1:2 and they are 256 x 256 miles. 512 x 512 miles map is too big to CT, because of 20-40 players. SEA maps can be both sizes.
6) Be careful when creating the map and test it many times flying there from corner to corner and looking the things are as they should be.
7) When you think your map is ready, you can contact some our Terrain Team member (for ex. me) and send your map files to us. We are checking it and give you the feedback!