Win 10 Pro, 3090/1080ti/1080ti, 64GB RAM, NVIDIA 460.89, Standalone 2020.2, C4D plugin 2020.2, C4D S22.123
I know it's a bit obscure, but just ran into this.
- Make a new Composite Material
- Make a new submaterial in Material 1
- Go to the Basic tab and turn on Material Layer
- Attach a material layer (set to metallic for example) to the pin in the nodegraph