Hi Rick - - A few comments on the issue you reported.
I must have been one of the first to have installed the new 2.3.1 version (being in Australia gives me a time advantage). I know I got it early 'cos I did some work with PL 2.3 - then closed the app and re-opened it a few hours later - and was then presented with the update notice).
My environment is exactly the same as yours - as you advised here … but I had no problem with the installation. I downloaded the upgrade when prompted by PL 2.3. One difference, perhaps, is that I did a reboot before I installed the new version.
Regards, John M