Normally in his characters, using Sagat as an example, you'll see a Statedef under the Projectiles in Helpers.cns called Hit Pause, these lines of code, for example, will be present.
[State 1011, HitSound]
type = PlaySnd
trigger1 = MoveContact = 1 && NumTarget
trigger1 = !(Target, HitShakeOver)
value = ifElse(MoveGuarded, 130, 2), ifElse(MoveGuarded, 0, 6)
channel = 3
ignorehitPause = 1
[State 1011, Hit Spark]
type = Helper
trigger1 = MoveContact = 1 && NumTarget
trigger1 = !(Target, HitShakeOver)
helperType = Normal
stateNo = ifElse(MoveGuarded, 8001, 8013)
ID = 8000
name = "Spark"
posType = P1
pos = ifElse(P2Dist x < 0, 0, ifElse(P2Dist x < 20, ceil(P2Dist x), 20)), 0
ownPal = 1
facing = -1
size.xScale = 1
size.yScale = 1
pauseMoveTime = 65535
superMoveTime = 65535
ignoreHitPause = 1
Obviously you'll have to change the pos though and maybe sound too.