Grimrock

Ok, I just went down the first set of stairs, unlocked the gate that needed 2 keys, then I unlocked the door that needed keys in the same room as the crystal. The door leads to a teleport that brings me to another place with a scroll in the room, I go down the hall and get stopped by a gate! I can't find a button anywhere, I've went back to the room with the crystal and nothing, checked all around and nothing! aahhhh am I missing something? Here is a picture
EDIT: spoiler-tagged the map -- Sol_HSA

well, back to roaming around, I'll be back in a bit

hahahahaha omg! I'm so stupid, ok thanks mate. Can't believe I overlooked that