The rear hatch on my 928 is either misaligned or twisted. Looking from the back the LH side sticks up slightly; in fact so much that the rear wiper motor does not engage with the mechanism on the hatch. If you press down on the LH side the wiper works and the hatch sits much better.

There is no obvious way of adjusting this; cant see that loosening the roof mounted hinges will do much and adjusting the screw in/out rubbers stops at each corner has no effect. Ideally I need the locking mechanism to pull the hatch in tighter to the body; there is no in/out adjustment on the body or hatch to do this only forwards/ backwards adjustment which I have yet to try.

Any idea?

Have you tried adjusting the support stop things which are halfway up the hatch opening?

The slightly more ham fisted approach if all the shutlines etc are looking good would be to open the hatch and try to twist it back into sitting correctly. Proceed with care and move slightly, check, repeat if necessary, check etc and this may cure your problem...

Either way I can't see it being too difficult to repair!