Thanks for your words !
I suppose nothing can be done to solve it. Sorry !
Most users (me included) have these mesh/transparent polygons disappearing instead of getting them white so it can be played with no real problem. (I'm personnally using a GTX-1070, win10, and haven't updated my NVidia drivers for a long time)
The use of shaders brings this bad effect.
Using only the "Mode_0" shader eliminates this but, except for the cars, all my other textures will be killed.