I'm trying to add more fields the workflow audit included in Summary Tab.
I added in the rule TC_10_Crf_Audit_WF_TIE properties fnd0AliasTaskName and fnd0Assignee and then I added them to the XMLRenderingStyleSheet the columms are in the audit but in blank.
What's the way to have this fields in my audit?
Possibly. The report just uses a Property Set retrieving values for properties on Fnd0WorkflowAudit. You could try creating a Closure Rule that navigated to the EPMTask and then add your EPMTask properties to the Property Set.
The report uses TCXML, so the Closure Rule will have to be TCXML.