The main interior light in the roof are known for going...the early MK5 ones was made in Italy...honest! The switch is known for arcing and burning out. I had to buy a new one when I got mine. The new one is stamped made in Germany funny enough.
Symptoms -
* Footwell lights STILL work.
* Opening/closing the doors still trigger the footwell lights.
* Both front and rear roof lights NOT working.
Hope that kinda makes sense as a rough guide.