OK , here is my constructive criticism
This was a pretty good movie and entertaining at pretty much most of the movie but here are a few things which I believe you should work on :
-The animation : I know that you've used tweens for pretty much all of it and there's nothing wrong with that provided it fits in well with the scenes . The problem here was that in some parts ... the movement seemed awkward and choppy ... like... the way the boy moved ... I think maybe you should have had made more models for the arms and legs ... split 'em in more sections sections ( i.e legs : thighs , feet ) ( i.e arms : forearm , hands , fingers) so you can have a more smoother and convincing tween movement . Also , it wouldn't hurt if you practiced some frame by frame animation and shoved it in to add to the mix!
The fire part : This is one of the parts where I got a major gripe with : Why was the boy not worried?! I mean , he's stuck in a house that's burning on fire and he could've gotten killed .... and yet , his facial expression seemed "not worried" ... I think you should take care of that and make sure that doesn't happen next time because you want the scenes to be as credible as possible .
- The fighting scene : Once again , this goes back to the animation part... It suffered in quality because of the improper use of models and maybe if you had done it in frame by frame ; you wouldn't have none of these issues . I cannot stress how important it is for a tweened animation to have all the body parts properly separated and synched ... hopefully , next time ... you will separate the legs and the arms in more parts to have a more fluid movement .
Well , this is it .
I wish you good luck on your next installments and your future projects . Take care