Tilt controls not working properly in 1.1?

[Tiny_Clanger]

I had tilt controls working fine in the original release, but since upgrading to 1.1 the car is virtually uncontrollable — the screen tends to flick left and right rather than actually steering, and the throttle sensitivity seems way down even though I've moved the slider to the right.

Is it possible that it thinks the neutral position is somewhere other than where I'm holding the phone (ie it's expecting to be held vertically or some such?) I can't see any way of saying "I am now holding the phone in the neutral position, please recalibrate" so I don't know how it's expecting to be held.

(Neither analogue nor digital touch controls work for me, unfortunately — maybe on an iPad where I can still see most of the screen, but on the iPhone my fingers just block the view too much.)