Download and install r27 plus hub (I'm unsure of compatibility with older versions).

In Cinema 4D got to: Edit > Preferences > "Greyscalegorilla" and set asset folder location to the folder "Greyscalegorilla Plus - (Mar 2023 Update)". You can also just merge these new assets with you old assets folder.

NEW: TACTILE COLLECTIONS
Using our Tactile Capture Process, we’re bringing you 5 brand new Tactile collections of the most beautiful and realistic 3D materials. Today, Plus Members have instant access to:

Polystyrene – A set of 15 absolutely realistic styrofoam-like materials ideal for abstract motion design or packaging renders.
Fabric – 55 beautiful and bold fabric materials meticulously curated by our design team
Felt – A set of 40 felt materials great for character design, fabric simulations, or abstract animation.
Architectural Carpets – 25 curated upscale carpet materials, carefully chosen by our in-house design team.
Colored Fiberglass – A set of 10 fiberglass materials great for 3D tables and chairs, or to add just a hint of fun, colorful nostalgia.
NEW: MATERIALS AND TEXTURE COLLECTIONS
Stay up-to-date with the latest trends and add a touch of realism to your renders with these three new packs:

Paracord Materials – A set of 70 colorful and contemporary paracord materials ready for your next rope simulation.
Plastic Materials – A set of 50 colorful plastics, fully customizable and perfect for lighter, more playful designs.
Surface Imperfections: Frost – A set of 10 tileable frost texture maps to add a little cool to your 3D renders.
NEW: HDRI COLLECTION
Introducing HDRI Creative Spaces – A set of 25 high rez HDRIs shot in beautiful creative studios, including our own Greyscalegorilla Annex. With large, soft light sources these HDRIs are perfect for tasteful motion design and product visualization.

https://greyscalegorilla.com/