Now at the beginning of the code there's this.

Code:
DS Activator Code
94000130 XXXX0000
Here's the part that I'm useing to help with the exp.
Code:
DS Activator Code
94000130 FCFF0000
*I put in FCFF to help with the example
Now on the second line FCFF. That's that activation code that it uses. Here's a list of all the activation codes:

Button Activator's
- - - -
NDS Activator Values
FCFF = L+R
FFFE = A
FFFD = B
FFFB = Select
FFF7 = Start
FFEF = Right
FFDF = Left
FFBF = Up
FF7F = Down
FEFF = Right Trigger
FDFF = Left Trigger
FBFF = X
F7FF = Y
DFFF = Debug Button
7FFF = NDS Not Folded
(If you want to mix buttons do the formula A+B is FFFE & FFFD so the button combo for it is FFFC so the different between the two letters is what it increases the digit by!)
All you need to do is change those 4 digits. Now I'm going to make it so all you need to press is L.
94000130 FDFF0000

I'll use the PokéBall Modifier code for a better example. Here's the code:

Code:
PokéBall Modifier
94000130 XXXX0000
02233FCC YYYYZZZZ
D2000000 00000000
*X's Activator Button, Y's Amount Of PokéBall's, Z's PokéBall ID
Button Activator's
- - - -
NDS Activator Values
FCFF = L+R
FFFE = A
FFFD = B
FFFB = Select
FFF7 = Start
FFEF = Right
FFDF = Left
FFBF = Up
FF7F = Down
FEFF = Right Trigger
FDFF = Left Trigger
FBFF = X
F7FF = Y
DFFF = Debug Button
7FFF = NDS Not Folded

I'll use L+R to make it easy.
Code:
PokéBall Modifier
94000130 FCFF0000
02233FCC YYYYZZZZ
D2000000 00000000
*X's Activator Button, Y's Amount Of PokéBall's, Z's PokéBall ID
YYYY = Amount Of PokéBall's
- - - -
0001 = x1
0010 = x16
0040 = x64
0100 = x256
0200 = x512
0300 = x768
0384 = x900
03E7 = x999

I'll use x999 again to make it easy.
Code:
PokéBall Modifier
94000130 FCFF0000
02233FCC 03E7ZZZZ
D2000000 00000000
*X's Activator Button, Y's Amount Of PokéBall's, Z's PokéBall ID
ZZZZ = PokéBall ID
- - - -
0001 = Master Ball
0002 = Ultra Ball
0003 = Great Ball
0004 = Poke Ball
0005 = Safari Ball
0006 = Net Ball
0007 = Dive Ball
0008 = Nest Ball
0009 = Repeat Ball
000a = Timer Ball
000b = Luxury Ball
000c = Premier Ball
000d = Dusk Ball
000e = Heal Ball
000f = Quick Ball
0010 = Cherish Ball
0240 = Dream Ball
01EC = Fast Ball
01ED = Level Ball
01EE = Lure Ball
01EF = Heavy Ball
01F0 = Love Ball
01F1 = Friend Ball
01F2 = Moon Ball
01F3 = Sport Ball
01F4 = Park Ball

Now I'll use Dusk Ball's cause there my favorite type of PokéBall.
Code:
PokéBall Modifier
94000130 FCFF0000
02233FCC 03E7000D
D2000000 00000000
*X's Activator Button, Y's Amount Of PokéBall's, Z's PokéBall ID
So now the code is done and it look's like this as our finished code. (Activator Button, Amount Of PokéBall's, PokéBall ID)

PokéBall Modifier
94000130 FCFF0000
02233FCC 03E7000D
D2000000 00000000
*X's Activator Button, Y's Amount Of PokéBall's, Z's PokéBall ID