hi there, im kinda stuck in the game. after beating the big ugly fella in level "the arena" you get to the "arena tunnel". after a bit wallrunning/jumping around you get to the point where you can slide down a ladder and beneath is a drop-dead-hole. jumping of the ladder gets you to a door. it seems the character cannot do anything in this area. im simply unable to pass the door, no switch no nothing. i must be blind a little help please?