If your still stuck, you can use these-
http://dl.dropbox.com/u/22173473/muzzle.rar
<img src="http://dl.dropbox.com/u/22173473/muzzlepic.png">
It contains 3 PNG images with transparency and instructions.
I made them for a shooting game i am working on.
I used these events -
Line 7 + MouseKeyboard: On Left mouse button Clicked
-> System: Create object muzzleflash on layer 2 at (gun.X-6, gun.Y-20)
Line 8 + muzzleflash: Any animation finished
-> muzzleflash: Destroy
The animation settings were -
Animation speed 50
Loop OFF
Repeat # 2
Repeat to 1
Ping-pong OFF
if you want to download the game cap (you can copy them out of the cap) go here-
http://www.scirra.com/forum/viewtopic.php?f=4&t=8778#p67345
Feel free to use them if they want.