I didn't see that the question was answered, but this is my issue/question (the same this user).
For all existing posts (prior to installing this plugin), we need to use or at least MIMIC the original form used to create & edit a post as normal (e.g. when I click “edit” go to the edit post page and not a WP user frontend form). If there is NOT a way to do this, then I think I can create a form that is essentially a copy of the interface and then if the admin needs to use further tools they can access the post via the dashboard.
Just wanted to make sure I am understanding what is happening.