can someone explain the credit invoice system with pdf order center since I don't seem to get it... what does this mean: "At least one selected order does -yet have a credit number. Are you sure you want to create a credit number for every order in the orders list?"? why do I have to create a number for every order? Basically I just want an invoice with a minus sign in the total for a cancelled order... And I don't have test store so I don't want to lose all the order data..