The Saga…

1. I booted in to the volume with the Supplemental on it to ascertain if my password would work as as I presumed.
2. I then concluded (perhaps foolishly) that something must be interfering/conflicting when I entered my PW in Terminal.
3. So I rebooted in Safe Boot and then tried to execute the commands as suggested. And voilà. The file is again hidden. Good news me thinks, indeed a very clever chap that Harvey guy…
4. But speaketh not too fast. When I attempted to boot out of Safe Mode, I discovered the volume was no longer bootable. The "mach_kernel" was not made invisible, it was deleted!
5. My vocabulary was then exercised to its full…
6. I have now replaced the "bad" volume with a known (pre-Supplemental) volume and all is again, right with the world. At least for now.
7. Perhaps I had a corrupted download--I really haven't a clue, only guessing. For sure I'm confused. Not since 1984 have I had such grief with an updater.

By the time I recover from this mish-mash, Mavericks will be released; and I am certain to give it go. In any event, the new OS will again be on an external backup.


Harv
27" i7 iMac (10.13.6), iPhone Xs Max (12.1)

Those who can make you believe absurdities can make you commit atrocities. ~Voltaire