Hi,
in general please avoid mixing different issues in one single thread. From the experience this has shown that there will be to many confusion about the different issues and people tend to add even more confusion when jumping into the thread asking for stuff.
This is expected behavior as you're not supposed to modify data within the data directory of ownCloud for the reasons explained here:
See the following thread containing infos about this "Unable to move" issue.
However i strongly discourage you to use the updater app as this is known to be broken for longer time. Instead do the manual upgrade like 8.2.0 -> latest 8.2.x -> latest 9.0.x -> latest 9.1.x . Instructions for this are available at doc.owncloud.org