HeadLookController

I downloaded the HeadLookController Extension from Unity site. I am having 2 issues. One is I get this error message when I press play. The only thing different from the demo project is I have other character controllers and scripts setup on the character so its possible that that is interfering?

 NullReferenceException
 UnityEngine.Transform+Enumerator.MoveNext () (at C:/BuildAgent/work/6bc5f79e0a4296d6/Runtime/ExportGenerated/Editor/BaseClass.cs:1016)
 HeadLookController2.LateUpdate () (at Assets/Scripts/HeadLookController2.cs:79)

My other questions is there a way to get the head to look at game object instead of the cursor. Is there a way to set the target?

Basically what I am trying to do is attach this script to NPCs so when My characters walks by they will turn their heads to look at him and I can't figure out how to do so.

Thanks for any help