Standard Assets unusable - Trying to use the ThirdPersonController Prefab

Hi Everyone,

I've been trying to get the standard assets component in Unity to work but I've come short handed. I'm trying to use a third person controller prefab in the game scene to use as a trigger to cue different music scores (with the help of FMOD) when the player steps into a different area but I just can't get it to work in the game window. I've attached a photo on what the issue is. The bottom right hand corner tells me the associated script could not be loaded. Now I'm a complete beginner at coding, but is there anyway to fix this? Thanks again for any sort of input.