So as far I can understand is what Sam has done, is that he has inactivated the control of the mouse so that the camera would not be free moving and he has dis-functioned the arrow keys because, every-time I would use the arrow eyes it would send the game into a glitch and not allow the character to move left to right, front & back; vice versa. The keys you can use is the space bar to jump and the W,A,S,D keys.