I noticed a weird bug where sometimes the game will auto-move for a player. In particular, this seems to happen when one queen captures a piece, and the opposing side has the ability to capture that queen with their queen, the game automatically makes the 'queen takes queen' capture.

I really like the sound effects. Especially check.

Thanks, I made them with GarageBand and Audacity, I think. The check sound is made from a recording of my girlfriend with added echoes ;-)