To clarify my response, once a setCustomerID call is made with an authentication state of authenticated, the Customer ID is associated with the 'mid' used in Analytics. This allows you to view various reports in analytics associated with the ID like Customer Attributes. If you wish to use Target to act on this ID, the ID will need to be set on each page and must be set to authenticated for Target to take action.
Did you still need additional assistance with your original question? If not, is there a reply that we can mark as correct in case others view this post?