I tried to append it to renderpath like in demo with GrayScale and I have all screen green
RenderPath@ effectRenderPath = viewport.renderPath.Clone();
effectRenderPath.Append(cache.GetResource("XMLFile", "PostProcess/GammaCorrection.xml"));
//effectRenderPath.SetEnabled("GammaCorrection", false);
viewport.renderPath = effectRenderPath;
When I uncomment third line, program looks good but obviously without the effect. Changing effect name to old ones (EdgeFilter, Bloom…) works and effect is visible.
Win7 Opengl enabled