Re-installation Issue with Creative Suite CS6 and Mojave (10.14.6)

For reasons complex enough that I won't go into them here, I have need to continue using CS6 alongside the newer Creative Cloud applications. This has worked fine up until now, despite it limiting me to Mojave, until in the last month the application manager kept requiring me to log in every time one of the applications was launched – no problem until suddenly I was told that my 'trial' period was up.  The application manager simply loops around prompts (see attached screen image file).

I took instruction via email with Adobe to uninstall and re-install both CS6 (in trial mode) completely and the Application Manager, suggesting that I then launch a CS6 application in trial mode and re-enter serial number, assuring me this should work – unfortunately it doesn't, and I still am unable to access the software, and without any options to re-enter serial numbers.

Does any one recognise what is going wrong here, and have any solutions?

Cheers, Bruce