toy tracks (compatible and parametric)

My kid is 3 and we got toy tracks of various brands, including my set that was bought in the 50s that I myself inherited. I needed more to it, and I felt like doing some openscad programming. 

The openscad is fully parametric; if anyone wants to make a model that isn't already in the stls you can easily do so.

Feel free to play more with the openscad file too and share the results.