Did you get through this? You try to give the brain to the leprosy guy, which is the only empty station to begin with, and he tells you to go next door. So you push the brain to that one (it doesn't need to go in the bowl, just next to it), then move it away again to get through . After you've visited the brains portal, you need to go back to the guy selling the death certificates and he'll tell you what you need to do to get one. That's where the stone comes in. Then when you have the certificate, you go back through the brains portal and you can move on.