Hello,
You can add the Zetadocs factbox to the Customer card page, and this will display any documents captured on the Customer card. It is possible for the Zetadocs factbox to display other documents related to this customer (that were captured against other NAV records, for example documents attached to a Sales Order using Drag & Drop function, or an Order Confirmation captured using Save & Send function), but this is only supported when using a Zetadocs Capture Essentials edition.
More information on the different Zetadocs for NAV versions can be found here.
Kind regards,