I had success with my 3.0i following the Bentley instructions (page 113-2).

Drei Bond 1209 on the half-moon corners (corners only) and aluminum seams up front by the VANOS. Nothing else.

When torquing, what I found, which is what I think should happen, is that you first torque things down (lightly of course) as the hard surface approaches the hard surface, compressing and sliding the rubber. So there is a lot of turning going on until the hard contact first occurs. Then after that, the actual angle to get the specified torque value is pretty minor. Kind of similar to the oil filter cap.

If you reach the torque spec without bottoming out the plastic, I think that is a problem. If the plastic cylinder head cover (valve cover) is warped in between bolt holes, as it commonly is to some extent, you might have sealing problems, requiring a new cover.

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2001 X5 3.0i, 203k miles, AT, owned since 2014