Serial number transactions don't work in negative quantities with NZQWO.RUN  
 
Firstly, you can't select an existing SN with qty on hand. That may be because...
 
Secondly, it increments SN qty instead of decrementing it
 
Thirdly, is the qty is more than 1 the program dies before demanding the subsequent serial info, and then...
 
Finally, although the UOH register is decreased by the full qty, the transaction register shows only the first item
 
On a positive note, all of the BOM items get pushed back into stock in the right quantities (as long as they are not serialized)