Just past the statues that you needed to hit the pressure plates for to open the gate, if you keep to the left the (wider) path spirals upwards to the room with Carlin. However, the path branches and you can keep right to go down, then take a ladder down to a small platform where you can jump down to the section containing the door to Lovis' chamber.
So should I have gone to pay a visit to Lovis' chamber before I went to visit Carlin? Only I appear to be stuck with George (Carlin) in a room of buttons that no longer do anything. Stupidly saved the game after entering so I'm going to have to start from, almost, scratch if I am now stuck.
*wonders*
