Editing comments after posting doesn't seem to work. Comment box flashes but still shows the original comment.

Yep, that sounds exactly like what I'm seeing.

On another note, reading your reply in the Summit inbox and tapping on "go to post" in the context section results in the following error:

Client error. Code: 400. Message: missing parameters for post.

My "All subscribed" feed contain posts from several non-subscribed communities when logged into piefed.zip.