Raptor I tried your suggestion of making sure the terrain was flat and it was. Still not working.
I took a custom airfield I knew worked renamed it and put in the tile I wanted to my my rs road tile. It worked just fine. Then I went back in to OE deleted all objects moved the file in to texsrc folder, opened TE built it, put it in the game and the cell overlay was back. I think there must be some sort of requirement for a tile to work properly in the game what that requirement is I don't know. Could it be building requirements, barracks, ammo bunkers, or just a minimum object load out? If I knew this I would continue with the tile building a custom town. I just don't want to spend the time and effort to be disappointed, I can't afford a new monitor lol.