Eureka! Why didn’t I figure this out sooner? There is a fairly simple CSS way to force a caption (including an image caption with clickable link) to hang out directly under a Squidoo lens logo or an image uploaded into the text module!
Ta-da! Actual screencap of a lens!
Here. I have, of course, created a new Squidoo tutorial:
Squidoo Image Captions: Handy Tip
Of course, the easiest thing would be if Squidoo would add an optional caption slot for images.
But then, I suppose there’s no way to guess what height / style the caption slot ought to be. It depends whether you’re trying to make a photo credit or some kind of comment/description.