Change textures at runtime on object with multiple textures?

I have a cube with 3 textures (green, black and blue). I'm trying to make it so the original textures (green, black and blue) on my mesh (cube) change every 5 seconds. Only lateral textures will be changed (green to yellow, blue to red). After 2 seconds yellow and red textures will be changed again to original texures. I have a problem when new textures come back to original.. The problem is probably in "instanced" materials.. I have noticed in Inspector that one material just disappeas. Btw Swap routine works fine.

 public class Change: MonoBehaviour
 {
    
     public float coldTimer = 5.0f;
     public float warmTimer = 2.0f;
     public bool warming;
    
     public Transform myCharacter;
     public Texture oldTexturev1;
     public Texture newTexturev1;
     public Texture oldTexturev3;
     public Texture newTexturev3;
    
     private Material[] sharedMaterials;
     private Material[] myMaterials;
     private Material[] myMaterials1;
     private Material tmp;
    
     private float currTime;
    
     void Start()
     {   
         currTime = coldTimer;
         warming = false;  
        
         myMaterials = myCharacter.renderer.materials;
         myMaterials1 = myCharacter.renderer.materials;
         //Debug.Log(myMaterials[0]);
         //Debug.Log(myMaterials[2]);   
     }
    
     void Update()
     {   
         if(currTime > 0.0f)
         {
             currTime -= Time.deltaTime;
         }
         else
         {
             if(warming)
             {
                 currTime = coldTimer;
            
                 tmp = myMaterials[0];
                 myCharacter.renderer.material = tmp;
                 myCharacter.renderer.material.SetTexture("_MainTex", oldTexturev1);
            
                 tmp = myMaterials[2];
                 myCharacter.renderer.material = tmp;
                 myCharacter.renderer.material.SetTexture("_MainTex", oldTexturev3);
                
                 warming = false;               
             }
             else
             {
                 currTime = warmTimer;
                
                 tmp = myMaterials[0];
                 myCharacter.renderer.material = tmp;
                 myCharacter.renderer.material.SetTexture("_MainTex", newTexturev1);
                
                 tmp = myMaterials[2];
                 myCharacter.renderer.material = tmp;
                 myCharacter.renderer.material.SetTexture("_MainTex", newTexturev3);
                
                 myCharacter.renderer.materials = myMaterials1;
                
                 warming = true;
                 //Swap();
             }          
         }   
        
     }
    
     void Swap() {
         tmp = myMaterials[0];
         myMaterials[0] = myMaterials[2];
         myMaterials[2] = tmp;
         myCharacter.renderer.materials = myMaterials;
     }
    
 }

 

Download package here: http://forum.unity3d.com/threads/163146-Change-textures-at-runtime-on-object-with-multiple-textures