intelligent throwing

Hi every one

Am ugandan using c# to develop a simple first person ball throwing game.

1. I want the game to behave in a way that when I the camera throws the ball every time the ball hits the ground and Am failing to achieve that.

2. Also how to I add score GUIs and GUIText so as they work in c#.

3. My game is throwing the a warning that states "the referenced script on this behaviour is missing"

thanks and May God Bless you