Hey Aren,
could you change the default texture of your shader's to "black"? When I load my shop UI I have a lot of UITexture widgets representing thumbnails. I assign the corresponding textures dynamically at runtime and because I don't want the user have to wait until every thumbnail is loaded, I display the widgets immediately. Now because the default shader texture is "white" you can see a white square that later changes to the correct texture.
With the default texture is "black" this won't happen.
_MainTex ("Base (RGB), Alpha (A)", 2D) = "black" {}
PS: I could disable/enable the widgets when loaded but hey, why the hazzle when it could be that easy
