Thanks, it's going to take me a little time to digest your post, I'll need to reread it a few times. I did note though that in your screenshots above I see a Final Renderings and Shared Renderings button, but I don't see that in my instance. Do I need to make a change to my core database to see these, or is this dependent on some standard values setting in a template or perhaps a version of Sitecore (I'm on 8.2)?

That was it, thanks!