Warped Models

[piktack]

Hey everyone!
I've been looking for an answer to this problem for a while, but I just can't find one. So, I import a model into 3ds max, and if I don't change anything, and export it, the in game model is screwed up. I went back and reassigned every vertex to its appropriate bone, but the model in game looks the same! I feel like there's just something I'm not doing...
I'll I want to do is give a model from Amazon total War a spear instead of a bow. I thought it would be really simple. What am I doing wrong?

Here's a screenshot:

http://postimg.org/image/r44jo93vf/

[Gen.jamesWolfe]

terribly sorry no one looked at it till now, but here goes:

near as I can tell, you have a skin problem (the one that assigns vertices to skeletons), that is doing this.

alternately, you may have attached too many objects onto one bone (I've had this happen myself).

[Halie Satanus]

It looks like you've weighted the hands to the wrong bones, left to right and visa verse. I don't see any legs either so god knows where they are.. The UV map is out of alignment as well.

Bone weighting can be complicated at first, even after doing it a hundred times you can mess one up, my advice is to strip that model back and start again. More often than not it takes less time to start over than to find a problem you're convinced shouldn't be there..