We have creating new oOrder type (VOV8) with reference to existing Debit memo order type (Billing document create with reference to sales order).
while testing the scenario we have occurred following difficulty,
1) while creating new sales order 'Order Quantity' field automatically gray after enter qty & system given message 'Enter Target qty' we have required to system should be allowed to enter order qty instead of Target qty. In reference order type system allowed to enter order qty.
2) While selecting output type (VF02>Goto > Header>Output) system given error message "Excise Invoice is not created" I have not required to create any excise invoice because it is commercial order type.