I did not tighten them fully. They are metal nuts on plastic tapers. If you tighten them too far you will strip the plastic thread and then damage it, so, I tightened them until resistance was felt.
There are no guides outside of BMW that show how to adjust the roof. There are four rubber stops you can adjust where the rear shell sits on the mechanism arms, just put the roof into the service position to see these. Within the rear shell mechanism are some long nuts that can be adjusted but again these should only be adjusted if you know what the result will be.
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