You can add new zones by selecting "Additional data" > "Browse zones" > "Add zone" and following the zone wizard. The zone browsing view also allows you to control the persons assigned to a zone. Note that one person can belong to multiple zones i.e. moving a person to a different zone does not remove them from the other zone they are in.
Add new estates by selecting "Administration" > "Edit estates", enabling editing mode, selecting the level of the new estate and right-clicking "Add".
You can move locks, keys and other objects between zones and estates from within their respective browsing windows. Select the objects, right-click, and select "Change zone/estate."
If you want to remove a zone, make sure there are no objects attached to it. Otherwise, the removal will not be successful. Then, go to "Additional data" > "Browse zones", put "Editing mode" on, select the zones you want to remove, right click, and select "Remove".