The following pertains to relating entity items to documents.
When the Content Type is set to Entity Items, the wizard will prompt with the following screen.
Select the Entity Type that you want to create a relationship for from the drop-down list. This is the entity type the primary item belongs to.
When the Content Type is set to Entity Items and Related Content Type is set to Documents, the following options are available:
Document ID
Select Document ID if you want to map the value of item selected in the drop-down list to the document's ID.
Document Type
To configure a Document Type relationship: