This may be a known bug (or set of bugs) but I don’t see it clearly shown as such anywhere.
View > Binder Affects setting misbehaves.
The Binder Affects setting is not saved across Scrivener invocations. I usually set this to Top Editor. It always comes up Current Editor. This means you must manually reset this each time you start Scrivener.
The Binder Affects setting changes seemingly randomly while working. I usually set this to Top Editor. Some sequence of events will make it change back to Current Editor.
The labels, Top/Bottom, Left/Right, First/Second do not accurately follow the layout. It appears to require a click in an editor to make the labels present properly.