With much effort and trial and error, I finally located a problem report follow-up from NI that addresses the issue, though it still took a lot of reboots, super-user actions, terminal commands, and adjustments to the instructions. Fortunately, I have years of experience on Unix so I always had a good clue of what to do when things didn't pan out in the instructions:
https://community.native-instruments.co ... mac#latest
Probably each person's Mac will behave slightly differently depending on how they have set things up, but a positive side effect of going through this process is that I finally got superuser login to work again for the first time in years; I have been having to use "sudo" on individual commands, but that is the recommended approach for most things anyway.
I had to bootstrap my superuser login by using sudo to change its password. Kind of funny, really. Using "sudo" did not work for me, with the shell script provided above. I had to run it with "bash", but could only do that if logged in as "su" vs. using "sudo" on the command line.
After a few reboots as per the suggested sequence in NI's response, launching Native Access then went through several helper installations that had just been done on the command line, but I think it's all part of the bootstrapping to get it past the security walls.
Everything was fine after that, and now this new version is WAY faster, more responsive, and more correct in its display of my library status, than the older version. I am installing all of the Evolution Series updates and new libraries now, and also was surprised by how many other updates I have missed because they required Native Access v2!