Delete Record/RequestPerform without dialog prevents the deletion confirmation dialog box from displaying when the script step executes.
Make sure that the record you want to delete is active (use navigation script steps), and then use Delete Record/Request. If the current layout contains a portal, click anywhere on the record outside of the portal to make sure that no related record is selected, then use Delete Record/Request. Use the Delete Portal Row script step. If Delete Record/Request executes when a related field in a portal is selected, the user sees a dialog box that asks whether the master record or related record should be deleted.