If you want to change anything, you have to first extract the PBOs files. Then you'd change whatever it is you want to change, and then you'd repack the PBO file.
Now, I couldn't get the gate to dial slower (because I didn't know how to do it), so I did little tricks for videos. The sound is easier though, since you only have to put in your new sounds with the name of the old sounds and replace them. I did that for mine, and it sounded well better.
Cheers