Cool game! I like that the gameplay is so simple while the game is challenging. It took me a while to figure out why I kept restarting; I really like that the chess piece that captures you flashes, but a little bit of motion feedback (i.e. the piece moving towards your character) might help convey exactly what's happening more clearly.
The transformation tiles really spiced things up and are a clever mechanic. If this game had multiple stages, I'd probably introduce them in like the 4th or 5th stage just to smooth out the difficulty curve a little. It took me a little while to figure out what they did because the transformation was subtle and had no animation or sound effect -- the first time transforming from light to dark, I thought that I was under a shadow!
I liked that the music was soothing and did not distract from the game. The melody perfectly suits the game. It got a little repetitive, but perhaps a lengthier loop would have helped with that.
After I beat the game, my only disappointment was that there weren't a couple more levels. Nice work! :)
P.S. Zoe was adorable. I loved seeing her scamper about the board!