One of our first observations came from just trying a logo change with the existing theme. We were able to upload two (2) different images with exactly the same name. One had a transparent background: one did not. We were a bit confounded that one instance of the logo, at the top of the page could be loaded from an external source while the one at the bottom came from the gallery by clicking on a picture icon. Actually, both logo pictures have the same options available, which initially eluded us.
Changing the global title, in the manner described in the WYSIWYG (What You See Is What You Get) description in the video wasn't really the way it went. We found header object under the site menu and, with a great deal of fuss, was able to insert our logo and text.
We started out just trying to modify the existing pages, instead of initially creating a whole new design. That was frought with problems because the pages already had a title that was tied to a page name and apparently some search object.