The problem is that often I don't know what people don't know but want to know. So when I get an email question whose answer is not already posted somewhere, I make a wiki page and dump the info.
This stub is in response to some work I did this morning. In particular, lights in X-Plane often have visibility much larger than the objects they come with. This used to be true for the cars, but I broke the code in 921 and didn't notice. In 921 headlights do persist beyond the car object's visibility distance, but not by much. 930 will fix this, restoring the "string of lights" look on the roads at night.
I've also tuned the headlights to be visible from a wider viewing angle, to try to make them more noticeable from above. (In real life, the lights illuminate an area of the pavement, which is visible, but we don't do this.)
If there is a scenery subject that is poorly or not-at-all documented, shoot me an email and I'll stub out a Wiki page - it's a first step to getting comprehensive documentation.
(Note that I have not added pages for tutorial steps like "how do I add a manipulator to my object" because I am doing the tools work for ac3d now ... better to write a tutorial for manipulators the easy way with ac3d than to write one on the hard way - editing the OBJ - and changing it later. That is to say, I am trying to documetn tools, not temporary work-arounds!)