RenderTexture and DrawTexture using material is not working

EDIT: I fixed it! The default materials I was trying did not work, but using GUI/Text Shader worked.

I am attempting to draw a texture to my RenderTexture with a material shader using DrawTexture.

If I use a material it will not render, but without the material parameter it works just fine.

Is there a specific setting I am missing on the RenderTexture to allow using materials with DrawTexture?

 void Start()
 {
     brush = (Texture2D)Resources.Load ("brushes/" + mBrushName);
         
     brushMaterial = new Material(Shader.Find ("Unlit/Transparent"));
     brushMaterial.SetTexture ("_MainTex", brush);
 
     renderTexture = new RenderTexture(Screen.width, Screen.height, 32,
             RenderTextureFormat.Default, 
             RenderTextureReadWrite.Default );
     renderTexture.filterMode = FilterMode.Bilinear;
     renderTexture.antiAliasing = 1;
     renderTexture.anisoLevel = 1;
 }
 
 void Update ()
 {
     RenderTexture.active = renderTexture;
     GL.PushMatrix ();                                
     GL.LoadPixelMatrix (0, Screen.width, Screen.height, 0);            
         
     DrawBrush(Screen.width/2, Screen.height/2);
     
     GL.PopMatrix ();
     RenderTexture.active = null; 
 }
 
 public void DrawBrush(int x, int y)
 {
     Rect rect = new Rect((float)x,(float)y, brush.width, brush.height);
     
     Graphics.DrawTexture (rect, brush, 
             new Rect(0,0,1,1), 
             0, 0, 0, 0, brushMaterial);
 }