Thanks for your replies, guys. I resolved the problem by using the squares to measure the map image dimensions roughly, then resized the map image to fit the closest multiple of grid squares perfectly. Since the map images grid graphic was drawn on it mathematically rather than by hand, this method worked. It took a little tweeking to get the size perfect, but not as much as I had feared it would. Thanks for the idea with using the grid squares, Mrgame. I didn't do what you were thinking exactly, but the idea inspired the easiest solution for me. You get a cookie.

Thank you also G.o.D., It hadn't occured to me that you could read the actors positions. I'm still not sure how the character's script would reference the correct actor though. I'm guessing it would have to have some code to figure out where the nearest actor is, which delves into writing the AI for the characters. I'm not that far along yet, but I'm sure that reading actors positions will come into play.