Wow! Well done! Gameplay, art, audio are great.
This game is really nice so I'm not going easy on you with the comments:
brakes*
You're* doing great
I accidentally found out a combination that bridges over water, which I could use to complete earlier levels with ease.
I don't understand what the stars mean when a level is complete (I always get 2/3 stars it seems). I thought I had to collect the crystal to get the 3rd star but that seems impossible.
Would love a backspace button to delete one command as I mess up a lot.
I had a lot of trouble with turn left and turn right because it is xxz and zxx. I would expect them to be inverse from each other like zxx and xzz but that's just me.