Map Pos to an event on the map

I am helping Gamingstaff with his ant game and I need to be able to Map Position to a tile with coordinates determined by globals and have the tile's event call. This works fine on 3 games I have made but not this one. Any help?

I suggest you first go back and verify everything you did in the places where it worked. Then carefully study every aspect of the one that doesn't work. There's probably a step missing somewhere. Or perhaps a typo in the directions given. That kind of thing can screw up the process very easily.