Help with projectile

[Kologer0s]

I've been making a bow for some reason and the projectile I'm using is abit screwed. It sticks on walls and on players but if it's on a wall and someone walks on it, the arrows still do damage and they get stuck on the player so he can't move. Also for some weird reason the game crashes when you shoot an arrow on another arrow that is stuck on the wall. Please help : http://pastebin.com/avFm0SMH

Unless someone can make another new one that is working fine and scrap that newbie stuff , all help is appreciated.