Nice Work Dimitri, I also will transfer all my cars like this. Therefore I wait for the lighting unit of a new Austrian manufacturer that will deliver exactly this for each car possible as in the unit will be everywhere a own processor
I actually didn't use the 50710 capacitor (Kondensator) from ESU, for having constant voltage (Spannung) through the whole track as I didn't have space to fit it in the wagon.
Next wagon that I will install the interior lighting, is the ΟΣΕ WLABmh174 Schlafwagen (Akropolis Express A.C.M.E. HO, AC55245). Probably in this, I will find space for the capacitor.
Now, the change of the old WEIMANN short coupler with the correct long UIC-screw-coupler from WEIMANN again. In this way, the wagons will "read" / εγγράφουν (is the Greek meaning) the curves with no problem.