Thanks, martcol, but I couldn’t find any way to alter the User name etc in the Support Pages – it seems impossible. I had only just registered to rate the plug-in. This gravatar has never been associated with this User Name!
Also, I don’t understand why the reg form asks for both a User Name as well as one’s actual name (I noticed in the forums, some people had used their email addresses! which I know is required on other sites – very confusing). So this was suggesting that it may be wiser to have a pseudonym; and in that case the gravatar should match the User Name, not my email address that is not associated with WordPress, anyhow – very weird!
I think WordPress should respect their users’ right to choice and privacy. I would have used my regular name if I’d known they were going to broadcast my photo. There was not even a warning about that. Bad form design, in my opinion.