You make it sound easy Hybrid!
You can't change the
decal but you can change the explosion images. FPSC uses two images in teh explosion, the smoke and the fire. Go to the gamecore/debris location and find the files and change them to snowy images.
As for the weapon, a ball is simple and can be made within 2 seconds. Give it some normal/diffuse maps and a nice texture and you got yourself a fine snowball.
The sounds for snowballs are easy, blow into you mic for a second then shorten in up for an impact-like sound.
Help in a box,
==MeZo
"Any gift can be great, no matter how small, because it's not the gift that counts, it's the meaning behind it"
"Heaven for climate, Hell for company"