As another person said, I'm reluctant to open up the Loco as it's so delicate. I suppose I'll just have to bite the bullet in the end and just go for it. Either way, the instruction sheet seems to say that there's three switches underneath, but I can only see two and they're TINY (should have gone to SpecSavers!)
On the wobble, mine does it while it's running. Like so many others, some of the axle covers have come off and this must surely be related mustn't it?