Hi guys and girls!

I am trying to modify a specific sound in my personal version of the Warhammer Mod BOTET. The Ratling Gunners (basically Miniguns for the non-Warhammer-guys) are respresented by an elephant model using a mounted_engine.
My testing shows that the descr_mounted_engines.txt seems to be responsible for assigning sound. Here is the section:

type ratling_guns
culture all
class rocket_launcher
reference_points siege_engines/ratling_gun.modelReferencePoints
missile_pos 0.0 -1.5 -1.0
crew_animations
fire Crew_Rear, crew_right_load_1, crew_right_load_2, crew_right_load_3, crew_right_load_4cycle, crew_right_load_5, crew_right_load_4cycle, crew_right_load_5, crew_right, crew_rear_fire_idle
end
normal_shots 10 ;36 for the bad boy
shot_delay 6
shot_pfx_front ratling_effect_set
shot_sfx ANIM_Serpentine_Fire
When I delete the last line the firing sounds stop altogether. When I insert other examples from the file, such as "shot_sfx Rocket_Launcher_Fire", it plays a different sound.
So my question now is... where can I find the ANIM_Serpentine_Fire that is referenced here and how would I go about adding my own shot_sfx to the game. Any tips or hints would be appreciated.

Cheers