Stops are defined as individual signatories on a cover sheet. A routing matrix is composed of several stops, the last of which is always Complete (this is the archives stop)
You can modify stops from the Inboxes screen on the Tools menu:
This will open the Modify Stops dialog:
Each Stop must have an associated email address because this is where AuditTrail will get the email address for automated email notifications.
Don't supply an email address for the Complete stop. Doing so will cause a new inbox to appear in the treeview on the Inboxes screen called Complete. This is redundant as it will have the exact same information as the Archives box. It won't hurt anything but it will take a support request to undo it.
Note the last column: LEVEL. This corresponds to the grouping of stops in the INBOXES screen as such: (Of course you are not required to use any of them if you don't want your stops categorized.
At the bottom of the Modify Stops dialog there are two reports available. The first, Empty Email Report will show you any stops that don't have an email address associated. The second, Stop Email Report will run a printable report that shows all configured stops and their associated email addresses.