And now for the final: everything fits!
For me it was a nice trip to try out what is possible with 3D printing techniques. I used Playmobil rails, the simplest I know. But I certainly think that more will be possible in the future. With that, more complicated track problems could be solved. For those who are interested: I make the .stl files available (send me a personal message). Maybe somebody will be able to draw the sleepers with it. I keep myself recommended.