I don't know how well this would work on the Wii version but I don't see why I wouldn't. There is a room that contains the boss key on arbiters grounds and across from it in a quicksand pit and spinner marks on the side of the walls. On the ledge across from the key, get on your spinner, enter the pit then jump like crazy on it and you should be able to hook onto the wall with the spinner, now as soon as you get on the wall jump again or it will send you in the wrong direction. If done successfully, you will be able to get the boss key real easy and within minutes be fighting the boss, as the door is very near.