Okay, this system is an *ADDITIONAL* system to modify my muds worldmap. However, this could be ported to any-mud with a worldmap.
This loads the worldmap in 'grids', so my worldmap was a 3000x3000 worldmap (loaded from a .png file) so, loading a 50x50 chunk as required saves on memory big-time.
This is the code I developed to allow me to grid out my system. With some modifications, as I said, it could work for anyone with similar systems.