Just wanted to know if I should ignore this or if I should change it to sharedMaterial like Unity suggests. The errors are pretty annoying.
Instantiating material due to calling renderer.material during edit mode. This will leak materials into the scene. You most likely want to use renderer.sharedMaterial instead.
UnityEngine.Renderer:get_material()
UIButtonColor:Init() (at Assets/NGUI/Scripts/Interaction/UIButtonColor.cs:123)
UIButtonColor:Start() (at Assets/NGUI/Scripts/Interaction/UIButtonColor.cs:73)