When configuring a PDF Document Template, how does the system map form fields to ServiceNow fields?

In the base ServiceNow instance, how are User Criteria used?

How does ServiceNow know which HR Template to use on an HR Case?

The Knowledge bases searched for the Knowledge results section on an HR Case are determined by what?

Scenario: You have an existing ITSM customer who is now implementing HR Enterprise. In UAT, they discovered that they get an error message about a Read operation from the HR scope to the Global scope being denied. You have verified that each Script Include was written correctly.
What else must be done to allow the Script Includes to work in the HR application?