here's an idea
cmp rx , #0xC5
blt : PTR @i think that's "branch if less than, but i have no honest clue, but that is what it's supposed to be in my mind of crazy...
assemble that into a binary file
remove the : PTR part from the end (which should be only 2 bytes) since thumb uses shorts for it's commands/arguments afaik.
then in HW continuously search for those matching values and then debug at that area and see if it's accessed at all when messed around with the world-map or map-loading procedure. I honestly have no idea if thats possible, or which register to check though. lol i'm blubbering again, but i'm trying to contribute :D