If your flow contains subflows, instances for the work item types used by and defined within those subflows must also be defined in the larger flow. This requires that each subflow work item type instance be mapped between the subflow and the process flow. EPX can perform this task automatically.
All work item type instances defined within the subflows that are called by the process flow are listed in the Inherited Fields table. To map inherited fields to your flow:
Right-click the subflow work item type instance and click Generate Mapping in the shortcut menu.
The work item type instance is added to the Work Item Type Instances table, along with the fields contained within.
The default name of the work item type instance is in the format Source.Source Instance Name, where Source is the name of the source subflow, and Source Instance Name is the same as the corresponding value in the Inherited Fields table.
Each field contained within the instance has a name in the format Source.Source Instance Name.Field, where Source and Source Instance Name are identical to those values for the parent work item type instance, and Field is the name of the metadata field.