I've been playing Trailmakers this weekend. What a shame, it seems to be only 1 weekend kind of game. While the phisics is truly decent (with a few random instadeaths though), the entire game does suffer from the same problem as many engineering games. Once you gasp the basics, the game is prety much over.
https://www.youtube.com/watch?v=vD7Iz5J6OB4