I'm new to shaders and so I make a lot of mistakes -- which aren't even very obvious to me.. and when I switch from Visual Studio to Unity, Unity freezes up and won't let me do anything. No error messages are generated. There is an _Extremely_ wide range of things I can do that will make this happen. Just recently, it was because I tried to give a variable within CGPROGRAM, but outside of any vertex shader, an intial assignment. Apparently this isn't allowed, but there is no clear reason why, or any documentation on it. I've pretty much froze unity about 30 times since I started trying shaders.