The answer to both questions is not really.
As far as the additions to the SO Ack. form, you could purchase ISTS's EVO overlay product and the forms customizer and then you
could add them yourself.
As to the report for items shipped but not invoiced, it is VERY difficult to even create such a report as DBA is set up to look at an item as shipped ONLY when it is invoiced.....ergo the problem....