Have a look at Figure 2... it shows the little arm i was talking about... If you really insist on fixing it, you may have to buy the little arm or the switch if playing with the ever so minor adjustments doesnt resolve it. You can advance it ever so slightly which may resolve the problem.
Sorry this is the best picture i could find without taking the door panel off mind today :-)
Pelican Technical Article: Boxster Door Lock Mechanism / Boxster Door Handle - 986 / 987