Well i found the secret passage and the explosives and all that but cant find my way to the room with the key so i can open the chest in the room with the explosives. Is there another pressure plate or am i just going going crazy?
yes go down to the archway wall (were the two paths connect, you'll see a shelf on the wall by the archway) & on the piller on the right side of the arch in the corner is a pressure plat to open the wall.