OK, I give up! It still won't let me input 'nothing' (ie: a blank, or no title) into the title area of this Follow Me widget - so I've just eliminated it in my child theme style.css file. If anyone else is having this same problem, try using this code:
aside#ultimate-follow-me .widget-title {
display: none;
}
I can't guarantee it, as I'm a self-taught webster, but it seems to have worked for me!
You can also add in some padding to give it a bit of space down from a horizontal menu like this:
aside#ultimate-follow-me {
padding-top: 5px;
}
All sorted for me now - though I'd still be interested if anyone else has had this problem...