it's all in blend, are they both set as transparent materials ?
I noticed the same thing happening in the S800 (or was it the veloce)
I would look towards priorities, i remember reading a post about taillight and priorities being important in some cases
You have two priorities settings in Kseditor, one on objects, one on materials.
I think the object one is only in ksEditor, the order it lists objects. And the reorder button, that usually crashes the app!
I never played with the material one. Didn't have to yet... my car doesn't have much glass parts
As for the damages, i managed to make it work. I don't know how, i redid the exports etc.
But how disappointing. My aluminium normal map is not tremendous ok... but how the game handles the damages... or rather doesn't, it's sad indeed.