Nice game, cute artwork, theme and animation.
Unfortunately I had the same as ArtOfProgramming; in the level with 3 stations (red, green, blue) the stations are distanced incorrectly it seems - when you use the rail snap there's always a gap or overlap (which I assume is bad). I've tried to use several combinations curved segments, short straight and long straight tracks but with the same result. If overlap is acceptable, please add a message or text in the tutorial? Same if there's a button to adjust the length of a track segment.
Another thing: The background music is pretty loud and very repetitive so it gets on your nerves really quickly. An option to adjust the volume or mute the music would be appreciated.