Thanks to @TassieNZ
Got it working with his update, but it was still problematic.
Make sure you use only the main program and addon from the download package (which by the way is labelled 30-nov-2020), and make sure to deactivate and delete all previous versions first.
I'm in the habit of renaming plugin folders to disable them temporarily using my Plesk control panel, in case an update doesn't work and I want to reactivate a previous version.
BUT I realise now that some plugins continue to function even after the installation folder has been renamed.
Hope this helps.
Got it working with his update, but it was still problematic.
Make sure you use only the main program and addon from the download package (which by the way is labelled 30-nov-2020), and make sure to deactivate and delete all previous versions first.
I'm in the habit of renaming plugin folders to disable them temporarily using my Plesk control panel, in case an update doesn't work and I want to reactivate a previous version.
BUT I realise now that some plugins continue to function even after the installation folder has been renamed.
Hope this helps.