Ashley Did you changed something in r216 with loading Tilemaps from json files?
Like before I am unable to use SetTile at (x,y) on some parts of my tilemaps.
That's a part of one of my maps - it goes higher for few more cells. Red crossed area is where SeTile at (x,y) works fine, everywhere else nothing happens.
Basically it looks like one of the bugs, that was fixed some time ago comes back.