I tried this out... and I get a blank nothing when I add the action to the before first drawing Behavior. I'm using CopperCube professional version. Any idea why this is happening?
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Oh that’s actually not an issue with my Shader action. It’s a really annoying Glitch/Bug in Coppercube itself. You can easily fix it by moving all the extensions from CopperCube extension directory to a temporary directory, for example, create a new folder inside the CopperCube extension directory and move all the extensions to that directory. Now just copy the Shader Action only to CopperCube extensions directory and restart CC or reload the extensions and plugins, now you will be able to use the shader action normally, after adding the Shader Action you can move back all the extensions back to the Original CopperCube directory. Hope that will fix your problem.