So I've managed to find a couple bugs. They tend to show up after having played a few games already.
The first one I ran to was on the 8th board. When I started the level I tried dragging a piece (over a spike but I'm not sure if that would matter) and when I released it didn't recognize the move, and even after quitting the level and restarting it I couldn't make a move (or any any other level). Once I restarted the game things worked fine again.
Edit: I'm running into this one every second or third board now. The first game is always fine, the second is 50/50 on whether the first move can be placed or not.
Another time I moved a knight piece and the arrow from its hint stayed on the board for a few more moves (it was towards the end so I won before anything more interesting happened.
I think both times were related to dragging a piece and dropping it at a weird place (or time?). Minor issues since a reboot fixes it but might be something to look into.
Also RE: the AI, the last level is great example of how completely inept they are (especially regarding the extra obstacles). The only way to lose is to not win, there's no way for the AI pawns to ever make it to the opposite side.