FlaggedRevsConnector

Error: How can I set up in a namespace, where any page that is created must be reviewed (workflow) before being seen by other users?

Solution: You can create a new user-group for the review process (i.e. 'editorial office'). In the WikiAdmin preferences menu in section "FlaggedRevsConnector" you can select that new user-group in the dropdown-menu for the option "Show unstable pages for following groups". Users that are allowed to view this unstable pages have to be member of that new user-group.

Error: How can I set up in namespace where the namespace owner is notified when a new page is created within their namespace?

Solution: There is no certain owner for namespaces. Unfortunately there is no way to get notified if a new page in a certain namespace is created. But you can see all new pages listed at the Special:NewPages - and here you can set a filter according to a namespace.