You create model items and their associated WTParts only when a business object is active in session. Mark the business object for publishing from the Business Object Explorer. For a business object, the WTPart is created only for those objects that are available in the main and library nodes of the business object being published. WTParts are not created for objects listed under other nodes, such as interfaces and groups.

The following figure shows how the WTPart appears in Windchill.