Delivery Orders [Out] Form Process Button

In
Warehouse > Delivery Order > Choose one file / ex: OUT/00001
In Delivery Orders Form when we press the Process Button :
- I would like to add a new field ex: Quantity (Packaging)

Problems:
Actually i succeeded on adding up the Quantity (Packaging) field in the process form but the value of the field is 0, the problems is the value of the field won't show, like the value in the database.

Thanks