1. Put the Redshift Shader to Cinema 4D 2.lib4d file in library/browser/ in your current version of Cinema 4d. Restart Cinema 4d
2. Copy the tex folder inside the tex.zip file, open c4d, Then go to Edit/Preferences/Open Preferences Folder and paste the textures in a new 'tex' folder . (If you have already the folder tex, just paste the files textures there.
3. C4D, Edit/Preferences/Files. in 'path 1' choose the path of 'tex' folder.