dankVinyl, In our next update the Windows version should confine the cursor to the game window (or screen) when not 'tabbed' out of the game. We are currently looking into getting the same functionality out of our Mac build, but it is currently a limitation of our game engine.
Our update should be released on Tuesday, August 30th. If you do happen to try the new update, I would really appreciate your continued feedback. Thanks again!
-Ryan