Use Weemapcache and search the iz_ac02. You'll see on the preview that the center of the map that connects all rooms is misplaced, that's why you can't walk alongside the mid. You can warp to the map and will end up in any room, but you can't left cause there's no pathway out of the room. I fixed this by adding a fixed iz_ac02 manually to the grf, and then mapcache assining the grf with the correct map.