No apologies needed! 
My nodes do not include functionality for resaving as central, so I don’t think Rhythm solves this issue at the moment. If there is any questions regarding how my background document nodes work, Rhythm is open source and the code for Application is here, .
This dialogue is not showing up for me when a document is opened in the background.
Unfortunately, I think that is all of the help I have to offer right now. I do have some updates for Rhythm background document nodes coming, but they are more of a “Stability upgrade” as referenced in the thread here.