Thank you so much for playing and for the feedback! I'm glad you enjoyed the game.
The Q and Z movement keys were included because, in a previous game I made, I used the standard W, A, S, D controls and later discovered that some keyboard layouts use Z, Q, S, D as the default movement keys. Since then, I've tried to support both layouts so more players can enjoy the game comfortably.
I actually played and rated your game not long ago, and I thought the concept was fantastic. Keep up the great work!