You have twist with a 30 force in an updating event, that would be the problem I think. Because unless you are clicking very quickly after the 0.5 secs, it will start twisting those actors very rapidly, I'm not sure that should cause it to freeze but definitely hurt the frame rate. Just a guess though from what I see, if you only want the actor to twist once, add another boolean check or set the turns off immediately in the updating event rather than waiting for the mouse click.