Ohh, I didn't realize the sign was telling the key to use ...
It is really missing a retry system, as it is very easy to get stuck with the cubes. I started the game 3 times and got stuck 3 times, so I gave up, sorry.
Thanks for the feedback! If you walk back away from the cubes far enough, the cubes will reset to their original positions. Yea, after getting people to play this, I'm starting to realize I may have made this too difficult and did not have enough explanation.
