Interpretation:
As you can see on this Activity Diagram, action states (activity to activity) are connected with double-sided arrows (red transitions) to show that several actions can occur, one after the other (e.g., once a task "Info updated" is accomplished, the administrator can "ADD user info" or undertake any other desired tasks.
In addition, our group added a horizontal Synchronization Bar to make these interactions possible. (Up to this point, our group is not certain if it is correct to create transitions having the ability of double-sided arrows; therefore, the Activity Diagrams may get updated more than once!)