Nice work and big contributions to the LFS community
Sorry I have a few comments...I hope you don't mind.
I have only downloaded and looked at the FZR settings. To my opinion, it is a bit dark, especially on the side and rims.
The map used on the skylight doesn't do much in this setting, because it is not using that image for environment reflection. It can do with just adjusting the colour of the skylight. Also I have notice that you have used 'screen' for the 'environ mappings', you should use either spherical or cylindrical for proper wrap around environment.
The rim at the moment is highly reflective raytrace material which only reflecting what the ground colour is, so if the ground is brighter, the rim will look brighter too.
I have replaced it with a Arch & Design material, medium blur glossiness/reflective.
I also replaced the floor with similar material to the rims, but with AO switched on. I have noticed that you have set the FG quite high, but for scene like this, you can reduce it down especially with reflective objects.
That is why I only turned on the AO on ground material, so that it gives a nice soft defused shadow underneth the car to compensate the lower FG details.
Your original file took 5 mins to render, and the modified image took 2.5mins to render. That is the difference it makes.
Anyone who downloaded the files and try to put skins to the car paint material, please remember, to get a good result, add the skin to both 'base colour' and 'light facing colour' slots. To be even better, darken the skin slightly for the 'light facing colour' slot.
My modified file is done in 3ds max 2008, so it is no good for many people. Therefore I will not submit anything up here. Especially bmwe30ms has already done such great work for starter.