As nobody in this so-called “community” could be bothered responding to my above post, I decided to contact the plugin makers directly with the same queries.
I did this on July 1st, and received an email acknowledging my enquiry.
To date (July 6th), I have no reply, and I have decided to stay with my existing email programme.
The upside is I have not wasted my money on a product which obviously has zero support or interest in new customers.
I suggest that anyone who is considering purchasing it take note of my experience.