Strange Animation Problem

[scorcher9910]

I'm trying to replace a model of a character with an imported model.
When the model's TransN bone is named "waist" the animations work fine, but the character runs in the ground. (By the way, the TransN index is the same for both models.)
I tried renaming the "waist" bone to "TransN" but then the animations got really messed up.
The strange thing is, on the other models that use the same animations, their TransN bones are named "TransN" and the animations work perfectly fine, exactly like the animations do when the new model's TransN bone is named "waist".
Any idea how to fix this, if you understood anything I said? Sorry, it's hard to explain.