Great news! I think my case is solved. I have managed to code the mk4 to color and everything works as expected for the time being.
Thanks to everyone for the suggestions. Without your help (...and software) this project would have remained unresolved.
I was very happy yesterday until this morning that I found my sunroof leaking......due to heavy rain!!! Can't get any rest with this car.......

Anyway, thanks again for everything!