I wanted to make an tutorial for that but I guess I'm just too slow for you.

Great work. What about the new changes to the hit-sounds? How will they affect the custom sound?

The game hitsounds system centers the pitch at 50 damage.
That means if you hit with raven/violator (~20 damage) the pitch will be around 2, and if you hit plain rocket or grenade (100damage) the pitch will be around 0.5. Unfortunately you cannot change that (yet?).

You can preview in UDK how it will sound, by changing the PitchMultiplier value in the Sound cue properties. However, you cannot change the way it is going to sound ingame (because, as I said, the game will override that value with the damage formula).
If you really need to re-center the pitch, you will have to edit the sound at its source using an audio editor.

EDIT: Never mind! There is another line in "Cruzade.CRZInterface_ConfigContainer" that has to be set to the same value as sImpactSound....

"HitmarkerSound"
I feel little stupid for not seeing that before.

Once I figure out how to get the pitch centered the way I want it this is gonna be so great