The frontlights beam is obviously connected with the shadow object, it isn't another object. Are used two textures, a transparent one for the day times and the lights beam effect one for the night times, with the "_ni" suffix at the end of the file name. You can take it from another car that has it extracting its .ar file, if it's not locked, and importing in ZModeler the .pkg file.
About the front bumper, I mean that its height is too high compaing it with the rear one, and it's almost close to the ground. After have see a side picture of this car like
this I've noticed this thing. It could be pretty easy to fix, just squeeze it a bit, but isn't really necessary, thought.
For the interiors, make only the top part of the seats coloring them black, and as Zac says, put a driver model make it all black too. More, better make the windows more opaque since the car has half and simple interiors.