Thanks for helping troubleshoot. I sent it “manually” by entering the URL into your site here. I suspect that I do need markup on my post — that’s literally the first “reply” type and I didn’t make any special formatting other than treating it a bit like a “link” post.
I don’t think I’ll use replies often, but we’ll see. I’m much more likely to just old school link to a post 😉
I have a much more full featured micropub endpoint now, including media upload support, so expect more pictures!