Also, could you please tell me if these numbers:

calc mxa @NL * 6 * 4
calc mxs 10 + @NL*2 * 4
calc mxt 500 * @N

will have to change in my script?

What is the significance if 15 here:

if c gt 15 goto eskip
if ug eq 0 then

Thank you,
Mihaela