This patch allows the user to change the palette of the tiles that appear behind the player on the OW border. Version 2.00 allows changing the tiles themselves, as well. These changes can be applied per-submap.
It would be really nice to be able to change the rest of the borders palettes/graphics on a per submap basis. The layer 3 border isn't refreshed when transitioning maps via red exit tiles. Otherwise, it's a nice patch and could come in handy.