That’s an old version, the V1 version is the most recent.
Hmm, that’s not problem with the script itself, it seems to be a problem with how Rhino is set up on your Mac… any of those should run if you simply type “RunPythonScript” (no dash and manually browse to any folder and select the .py file to run.
In principle the scripts folder -
~/Library/Application Support/McNeel/Rhinoceros/Scripts is where Mac Rhino will automatically look if you use an alias without the full path being specified. That folder is a hidden folder, to get to it you press the Alt key and pull down “Library” from the “Go” menu then browse to that folder. Scripts need to be directly in that folder, not in a subfolder and have a .py extension.
Otherwise, for aliases, you can also specify the full path to the script file no matter where it is located.