Procedural Texture not working on iOS

From what I read at http://unity3d.com/unity/whats-new/unity-4.1, procedural textures are now supported in iOS. I created a simple test quad to animate some lava swirl and it looks great running in Unity Editor. However, when I build for my iPad Air running iOS7, the quad renders a blank black. What am I overlooking? Thanks, Manny UPDATE: Is this the error that Xcode is throwing: OpenGLES error 0x0502 in /Users/mtran/Documents/Unity/MyUnityApp/iOSMyUnityApp/Classes/Unity/GlesHelper.mm:373