looking very nice so far mr pix
The only thing that caught my eye was about the beginning to the end of 9 seconds in. When he pulls the box the second time there is a lapse in his action that would have resulted in the box dropping back down to the ground (based on the weight that you have given the box overall). If you made his action of stopping the box more exaggerated and faster then it would help.

still very good stuff though
Simon