skip the glow on the headlites - otherwise they're gonna be glowing all the time.
modern vehicles have got a molded polycarbonate "lens" which, due to the index of
refraction of the plastic, has got fresnel ridges molded into it.  altho C6pro (and likely
c5 as well) cannot use refractive models to affect a lite cone in any realistic manner,
it's better to model those fresnel ridges into the headlamp cover (the "lens") IMVHO
rather than trying to use some texture/displacement method.

older headlamps use a standard tungsten filament, whilst newer ones appear blue,
as they're HID lamps which emit a great deal of UV lite, very hazardous to look at;
yet another example of a total lack of any governmental oversight in regard to
public safety.

in c6pro, select the spot, then open the "effects" tab and edit the light cone to get
falloff, add gels to simulate the fresnel ridges, add lensflare and glow (light sphere),
add turbulence et al.  it takes time to understand all those things.