Hi Marc! And welcome here!
After 2 more releases there will be a documentation explaining how to do many things.
Currently I would suggest to make chrome with 2 reflection channels:
Reflection 1: color = white, roughness = 0.2, IOR = 1.3
Reflection 2: color = white, roughness = 0.6, IOR = 1000 (totally outweights all underlying layers like diffuse and others).
You may optionally add scratched bump for Reflection 2 only. Just make bump and uncheck it for Relction 1.