C4D files do not import their materials in a really meaningful way.
Graphisoft have a specification and map them into the library as .gsm parts.
Until we see the spec, and I've been asking in several different places for this, it will be a challenge to expand the ArchiCAD CineRender Surface Collection from the abundance of C4D textures out there.
Still working on this.
Think Like a Spec Writer
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