Hey,
since the update we have a problem with the current NGUI version (3.0.6f6) and Substance materials. We create procedural textures using Substance and are applying those to a UITexture-Component as the MainTexture (we tried to use a Diffuse-Shader, as well as a Unlit - Transparent Colored-Shader for the UITexture). On the PC this is working, but on the mobile device the texture is not visible at all (only a "blank" - white texture is applied). It seems that either the texture is not applied or it is not redrawn correctly. Or maybe the Substance material is not compatible with the UITexture-Component.
PS. since the update (from 3.0.5 to 3.0.6f6) we also have a lot more DrawCalls in some scenes. We did not change any Depth-settings of UIPanels or Widgets. Don't know what the reason is for this behavior.