RH-55601 Rendering Materials: Various default Render Content cannot be loaded or is corrupt
should be fixed in the latest Release Candidate for 6.21. On a “fresh” installation of Rhino 6 for Mac 6.21 or later, this should just work.
However…
If you have already installed Rhino 6 for Mac and are experiencing this bug, there is more work to do.
When Rhino for Mac first launches, we copy the default Render Content to:
/Users/~/Library/Application Support/McNeel/Rhinoceros/[version]/Render Content
Once default Render Content is written, we never overwrite them. This is because we don’t know if they have been modified or not and we don’t want to overwrite customizations that are in place. However, if the offending file itself is deleted, 6.21 will replace it with a corrected version of the file that should work.
So, if you have customized your Render Contents, we urge you to selectively delete those offending rmtl files that were causing the problems. Once 6.21 starts, it will fix those materials.
If you have NOT customized your Render Content, it is safe to delete the entire Render Contents folder located here:
/Users/~/Library/Application Support/McNeel/Rhinoceros/[version]/Render Content
Once you restart Rhino 6 for Mac 6.21, this bug should be fixed.
Please let me know if you have questions. We appreciate your help reporting it and tracking it down.