The Security assist wizard will create a default rule for if the user is logged in named:
Logged into <your user table>
where <your user table> is the name of your user table.
When the user logs in, the ID is stored in a session.
The logged into <your user table> rule is defined as:
Value: Click the lightning bolt icon and select the Session created by the login
Criteria: <> (This means Not Equal To)
Comparison: (Leave this blank)
you can then use the security assist show region behavior to show the details if the user is logged in.