Please see the most recent updates in the "Where did the .com name go?" thread. Posts number 16 and 17.

It's an FSX bug.
Strangely enough it depends onaltitude and even location in FSX.
The DC2 has the lights slightly offset in for example Los Angeles.
The lights are all OK in e.g. Munich.
Toggeling views, and go through them all in rapid succession sometimes fixes the bug.
This is the same for model base lights, and for aircraft.cfg based lights.
We broke our heads on it, but didn't manage to get it completely right all the time.
Cheers, Rob