I haven't had any shorting problems. Seems like either keeping the strands away from the ceiling or putting an insulating material (fishpaper, etc.) would prevent a recurrence. Maybe even some Contact paper or a couple of layers of masking tape on the ceiling.
I did have a problem in the ceiling light of the rear bed, where the switch would tend to stay ON. After spending way too much time looking for a replacement switch, I decided to replace the entire assembly.
The manufacturer is Progressive Dynamics Inc.
The RV lighting products are at:
http://www.progressivedyn.com/_frame..._lighting.html
I found it best to call their Service Department (269-781-4241) for the parts. They were quite helpful and sent a catalog with the parts. Shipping was $7, but it saved me from more driving around..... Naturally I ordered "white" when all the rest of the ceiling lights are "ivory", but I'm the only one who's noticed :-)
I also ordered several replacement lenses as the forward lenses that contact the roof of the rear section have become quite dark and discolored. I plan to install the new ones at set-up and put the old ones back in for travelling.