It would be great to be able to see the relationship between invoices and delivery orders. This is because not all invoices have quotes and sales orders generated (e.g. customers who make instant purchases, such as buying now in e-commerce). I added a field for one-to-many relationships (invoice => orders), but the fields will not be filled in automatically (like delivery address, shipping provider shipping contact etc...). And one question shouldent the filed Items be filled also automatically?