Looks to be texture that hasn't been assigned properly in your materials file, Hope that fixes your issue
probably uses Covet assets then. https://www.beamng.com/threads/pre-remaster-covet.88151/#post-1500070 This is not a permanent fix, but it may fix your issue.
I opened the tool file but I couldn't find much about textures. I also opened it in Blender, but the texture is not even used.
there are some older mods that were fine before 0.26 and they all used their own custom assets, but now their glass texture is broken (Skoda 120/130 mod in particular, and you cant even fix it)
That mod used the Grand Marshal glass textures for some reason and they got remastered in 0.26 which broke the mod. A lot of old mods that people think are "100% scratch made" actually use lots of vanilla assets and are bound to break.
I found something and I think I found the missing files too. This photo is the files of the headlights of the old covet mod. This is Dacia's headlight and glass files. I noticed some textures are missing in the covet
oh, well i guess that makes sense, but its just that the mod worked fine for such a long time, honestly we are lucky that it worked for so long