Z-Code and Zebra Printing

Hi, we have a customer program, ZLABELS, and there are two inputs that determine the number of labels to print:

When "boxes" = 2 and "sides" = 2, 4 labels are printed; for any other combination, 3 labels are printed. The code is rather long so wondering if someone might help guide me on how to find out where in the code to look.

Thanks!

Jg