@AndreaZani905, I just saw your new question when I used this topic as a reference for a similar question.
The challenge will be with the modifier. I started to fully implement the modifier but for now you can create the last part (mirror with glass_angular_affect) as a custom material and add the other two material as a file to radiance_scene.
I start the implementation of modifiers and in the near future you can pass another Radiance material as a modifier.