Re product category: it’s glitchy. Sometimes I have to refresh the page several times, wait 5 minutes, and then refresh again.
I’m able to make changes after it’s published, but never the category 1st 2nd or 3rd tier. Sometimes that, too, takes several refreshes. But once it works, my edits stick.
So far I have 19 listings. I’d have more done if it wouldn’t glitch, because then I go off and do something else.