If you rename your Plone site on Plone 5.0.1 you will be unable to delete content, replace images, text updates work on pages but essentially it breaks the site. Reindexing the catalog does not resolve the issue, once site is renamed to the original name the issue no longer occurs.
Customer wants some fairly massive changes made to their site, import export site and rename the copy something else as to differentiate between them, new one now is incapable of making content changes.
Maybe it is a Zope issue, but put under core development as it is a fairly useful thing.
You can replicate this issue with a fresh zeo installation of the latest release of Plone 5. Just rename your particular site and try to insert an image on a page or delete some content.
I'll replicate this and add the traceback that is received for more info