I've introduced you the physics puzzle game, Fantastic Contraption on my previous post. If you are stuck at the map, you can check out my build. I'll post all solutions here. From map 1 to map 21.

1. Rolling Away - http://FantasticContraption.com/?designId=2781809

2. Reach Up - http://FantasticContraption.com/?designId=2782093

3. Mind The Gap - http://FantasticContraption.com/?designId=2782155

4. Junkyard - http://FantasticContraption.com/?designId=2787161

5. The Wall - http://FantasticContraption.com/?designId=2787414

6. On A Roll - http://FantasticContraption.com/?designId=2789065

7. Full-Up - http://FantasticContraption.com/?designId=2789353

8. Higher - http://FantasticContraption.com/?designId=2789571

9. Around The Bend - http://FantasticContraption.com/?designId=2789703

10. Up The Hump - http://FantasticContraption.com/?designId=2791181

11. Mission To Mars - http://FantasticContraption.com/?designId=2829280

12. Up The Stairs - http://FantasticContraption.com/?designId=2792502

13. Big Ball - http://FantasticContraption.com/?designId=2792877

14. Four Balls - http://FantasticContraption.com/?designId=2794762

15.Down Under - http://FantasticContraption.com/?designId=2735334

16. Awash - http://FantasticContraption.com/?designId=2740869

17. Handling - http://FantasticContraption.com/?designId=2743168

18. Tube - http://FantasticContraption.com/?designId=2746459

19. Back and Forth - http://FantasticContraption.com/?designId=2769549

20. Unpossible - http://FantasticContraption.com/?designId=2795978

21. U-Turn - http://FantasticContraption.com/?designId=2768886



These are my solutions....of course...it is not necessary to follow these...you can come up with a better idea which I couldn't think of.
By the way, you can view other solutions by Vince Cheong.