Mentioning this in case anyone else has a similar problem:
At each stage of “follow the steps” error messages appeared, firstly that other applications were using the eLicenser which they weren’t because I didn’t have any; a threat that only limited functionality would be available after I finally got past that.
I couldn’t understand what “Authorising” this and that meant and achieved it more by chance than anything. I thought accepting the licence terms and entering the activation code did just that.
Several other errors cropped up and the best response was usually to click the cancel button.
It has to be among the more misleading/complex installations I’ve done since Windows 3.1.
Quite honestly the step by step instructions could be fleshed out a bit.
Now trying it out.