Iit took me at least 10 tries before understanding how the game worked, but eventually I managed to finish it with a score of 17 :-)
Maybe you should put the 4 {N,S,W,E} tiles respectively {above, below, left, right} the current tile and bind them to the {up, down, left, right} or {W, S, A, D} keys to make the navigation a bit more intuitive.