C4D to unity with shaders

i have built this scene in cinema 4d r15 Imgur: The magic of the Internet
and this is how it looks after i exported it with materials and imported it to unity Imgur: The magic of the Internet

how can i get the shading right?

Lighting and shading doesn’t translate well (or sometimes at all) from a rendering package to a real time game engine. You should do the shaders and lighting in Unity itself.