Hi!
I know this is not the right forum. I will also post this in the Unity forum.
I just post it here anyway.
It's just a video to show my game in both Unity 5.4.1 and Unity 5.5.0.
It's just so frustrating that an Unity upgrade can cause problems in the game. Not only errors. In my case, is not errors. Well, just some warnings about the animations. It's about physic and Rigidbody 2D which has been updated.
https://www.youtube.com/watch?v=JVK01ZPcvbs&feature=youtu.be