I'm having difficulty downloading a gemstone toolbar

The gemstone toolbar is linked in this video. I downloaded the zip file and followed the instructions, but it won’t allow me to import the files into rhino.
The .rui file saved as a document, so I changed its settings to allow it to be opened with Rhino7 (previously was off) but it made no difference. Any ideas?

It just says error reading file.
Thanks

Hi Christine - just to be sure we’re on the same page, RUI files are opened from Options >Toolbar page > File menu and not from the top level File menu for Rhino.
I see this is on Mac, sorry, that is not the same in V7…
-Pascal