All you have to do for the collision model is open the original model, put a box around the scenery, delete the original model, and name it collision_model. Thats it.
For skinning...
Can you show us the model you would like skinned that might help.
So you just need somebody that has 3ds max to do it becasue they would be able to save as the right format? If this is wat you are saying, IM or PM me, I could help if you wanted.