Easy way...get weapon creator.
Difficult way..
Ok the GUNSPEC consists of the GUN files requirements such as the muzzle flash,sounds, and weapon type...
By
Quote: "animated version of your snowball"
your going to have to animate the snow ball in milkshape your going to litterally have to animate it in milkshape, that I can't explain how but if you want to know you can just google it "how to animate weapons in milkshape". Your going to also have to UV map the model, I mean you dont want a gray perfect sphere on your screen...that would make it look more like one of the super bouncy balls things rather than a snow ball..Texturing is easy, it is not going to give you a difficult time...
Now to get the right position for your model to come up your going to have to literally play around with the model until you get the right HUD position. The best way is to take a weapon out of the game that is already working, import it into milkshape and then use that as a ruler to position it.
On the side not you may have missed the creating of the HUD.X folder
which should be located in your gun folder in "gamecore\guns". the hud.x is the model that will actually appear on screen for you, the player to see...
to shorten my words heres a tutorial
http://forum.thegamecreators.com/?m=forum_view&t=116184&b=24
that i used when i first started, eventually i just worked without it..but it straightened the road for me to move forward
good luck,
moneytakea