@Michael everything is default really (both export and import) - you could post your default obj mesh and I will show you. Or, even better: in C4D assign metallic material, get closer and to the fillet and play with light direction. IDK how one could expect good results with such a problematic topology.
I'll try the the .ini trick tomorrow..
@PaQ at last Haleluya, thank you for confirming!
With Ngons situation is really bad (post 18), with triangulation - better (p#15)
@val2 you are fine because of the distance and maybe higher poly count, get closer to the fillet area, rotate the light and see what those triangles do.