The fact that you can't move in the same direction twice without committing to a move can feel a little frustrating, or that if your starting position can't move in a direction, you can't move in that direction until you commit and get a new starting point. You also never explain if a red square can move on your current position. Do I get to wait in the white squares, or are the yellow squares the only safe ones?
Edit: The answer is yes, you can get hit while sitting on a white square, the only safe squares are the yellow ones.
Edit 2: I think I saw a red square land on a grey square and kill it, not fully sure