The comics are unfortunately not in the Media Library. I will go ahead and add them there manually, and have a look at the attacher afterward. I’ll let you know how it goes.
After posting this and continuing to work on it, I have found a solution that seems to be working: If I set the comics category to a new category, and move the posts to that cat, they show up properly.
A pain in the butt, and I’m still not sure the cause, but it seems to be working.
Nevermind, seemed good for a moment and then reverted behavior.
