Ok, if you want to try the point is inside then put this anywhere in the setTile function outside of the for each tile. Since inside the for each you can’t reference more than 1 tile. I used the bounding box, so you wouldn’t need to know the tile size or where the points were and then added/subtracted 5 pixels just to be safe.
Again, I used random colors for testing. I enabled 1 event at a time.
red up-left, purple up-right, yellow down-left, cyan down-right (orange didn’t show well)
Edit: it seems to work and I didn’t notice any lag.