There's a pop-up ad of some kind that appears on this site, though I'm not even sure what it's for. The point is, it appears when I'm about to post something, and somehow or other actually PREVENTS me from posting anything. Has anyone else had this happen?

Thanks for the heads-up. I haven't seen it, but would be interested in whether others have. It doesn't sound like something they would do, or tolerate on purpose, over at Bravenet, especially as we pay for the "Pro" version of the Forum. Sorry to say it but one possibility is that it's some malware or misbehaving browser add-on at your end. I'll check the Bravenet Support site to see if others have it. Thanks as always for posting.

The last time I saw it, the posting problem didn't happen, so MAYBE it's just something I do that's wrong. But, I don't know.