Nah, I've worked most of that out now - I think I now need to:
find out where to get more Oil for that second hinge to the pit. Anyone got a clue?
I feel a feckin' amateur here. The demo made me feel the same way.
UPDATE: It's okay, I found out what I was doing wrong. As usual with adventure games, 90% of time the answer is simple "I've missed something crucial". For some reason my monitor's auto-config cut off a portion of the right side of the screen, and so I never noticed:
Froderick's cage and the Nuts within.
Luckily on pressing Tab it was JUST within the screen, so I JUST noticed it.