This came up in a game I played earlier. My piece had move diagonal enabled, and was it the center of the partial board below
3 5 4
3 3 5
3 3 3
The numbers indicate the height of each tile, 5 being highest. I moved from the center 3 to the corner 4, which is currently legal, but I wonder if it shouldn't be? Graphically, the two tiles at 5 seem to block all passage to the 4 from that direction, implying that my piece would need to pass over at least one of them to reach the tile at 4. If the 4 tile was lower, of course, my piece could pass under the tiles at 5, so it really is just this case that could be said to behave oddly.