People still use him as a base, but mostly they use different characters. But If I can remember just find the hitsparks in the file that KFM has and replace with your own. One sec tho ill clarify after I look at the coding.
EDIT: Yea i'm pretty sure now. all you have to do is change the number for the hitspark in the hitdef of the attack once you have added your hitsparks to the .sff Not the fightfx.sff but your actual character's .sff like say rugal.sff but make sure that the name for your .sff is in the .def for the character as well.
here is a sample of my code for my character explaining it.
[State 2025, 1]
type = HitDef
trigger1 = AnimElem = 2
getpower = 20
attr = S, SA
animtype = Hard
damage = 100,5
priority = 5
guardflag = MA
pausetime = 12,12
[color=blue]sparkno = s9011[/color]
sparkxy = -20,-64
hitsound = S1, 13
guardsound = s3, 16
guard.sparkno = S8076
ground.type = Low
ground.slidetime = 15
ground.hittime = 18
ground.velocity = 0, -4
guard.velocity = -6
air.velocity = -2,-2
air.type = Low
airguard.velocity = -4,-4.5
ground.cornerpush.veloff = 0
fall.recover = 0
fall = 0
EnvShake.time = 12
Just look for sparkno then change the number s"number here" number here is where you put your spark animation without the "". S is the abbreviation for spark.
So basically the exact coding would be something like this : sparkno = s9011 like above. Just with the added coding for the rest of the hitdef. I hope this makes sense and is clear. If you need more help shoot me up.
Here is the code taken from my character's .def file as well showing the character's .sff file.
[Info]
name ="Shin2_Akuma"
displayname ="Shin2_Akuma"
versiondate =
mugenversion =14,04,2002
author ="xPreatorianx"
pal.defaults =1,2
[Files]
[color=red]sprite =Shin2_Akuma.sff[/color]
sound =Shin2_Akuma.snd
anim =Shin2_Akuma.air
cmd =Shin2_Akuma.cmd
cns =Shin2_Akuma.cns
st =basics.cns
st6 = Flash_Supers.st
stcommon =common1.cns
pal1=akuma1.act
pal2=akuma3.act
st1=specials.cns
st2=Helpers.st
st3=Supers.cns
st4=combos.st
st5=Flash_Supers.st
[Arcade]
intro.storyboard =
ending.storyboard =