Have a look at the sfz format, check the SFZ on the top right filter
https://sfzformat.com/opcodes/

Make a backup of C:\Program Files\PG Music Inc\Band-in-a-Box Sounds\Programs\Guitar\Nylon Acoustic.sfz
open the original in Notepad of text editor by dropping in.

I'm just trying to remember it all as I made a lot up in the User Forum.
In the file you will see

gain_cc7=18

I'll have a look more and see if it all comes back to me.