I have installed GP4 using the orig DVD along with the 9.6 patch and no CD v1.02. Utilizing a fairly new vVidea GX1030 video card, I set all the graphics to high settings and 30 fps. I get the "white" no graphics images on the rear and bottom of the cars. When I copied the whole GP4 with these updates off of gp4central and run it with the same graphics settings it works just fine. Cannot figure this difference out. Any thoughts?
If you are using CSM, there is a "shared" folder in the Cars folder which contains textures for common parts of the car. If these are missing for the specific car, then they will show as white parts as you mentioned.