I'm one anti cube and 9 cube bits away from 100%, and I'm totally stumped...
I need a key in order to open a door in the windmill stage, and the only other door I don't seemed to have opened is accessed from the sewer hub.
Looking at the default map without rotating, from the sewer hub it's up and slightly to the right, next to the room where you need to rotate the floating block on top of the swivelling platform in order to reach a treasure chest up high.
My issue is that I've completely scoured the sewer hub and can't find a way into this last room! Can anyone out there in GB land give me some advice and point me in the right direction?