Territory Assignmen - Using Custom Child Object

Summary

Not able to use custom child object in territory assignment

Content

As per the oracle note "Using Custom Attributes in Assignment Doc ID: 1921147.1" it is possible to use Custom Child object of Sales Lead object in territory assignment. I have followed the note and created a custom child object for the sales lead in application composer. Then I have released the sandbox as per the document to use the new child object in assignment object. But from the object assignment screen I cannot see the newly created custom child object when I click on 'Create Child'. Does anybody has any idea what to do to enable the child object in