2) Where in the XMLUI (Mirage) can I create a "Top-Level Community"?
In JSPUI there is a AdminTool under the community-list page. I can not
find this using XMLUI anywhere.
That was a bug in 1.7.0, and we just fixed it in the latest release 1.7.1, see https://jira.duraspace.org/browse/DS-840
You can alternatively click on "Communities and Collections", and if you're the admin user, you can create a top-level community there.
-- Peter Dietz Systems Developer/Engineer
Ohio State University Libraries