The coding for showing maps and the entire start a game window/gui was removed. This was because of the v21 update due to the fact that they had too much code. It would make future updates faster without terrain/interiors. Im pretty sure if they kept the maps with shaders, the maps would be really buggy with them. Also, there wouldn't have been enough time to put them in so they could reach the August 9th date. It would have happened possibly 5 months later if they kept the interiors and terrain.