yeah, this is the problem. the main frame, that makes it easy to get all anis work with a changed model. i am no coding guy, but some time ago i digged into this and surrendered to the complexity...every animation has its own coordinates from the vertices, that move. so by thinking logically on this, you would need to adjust every new vertice by HAND - impossible. the new animation also goes wacky, if the new model has more vertices, than the old one. maybe the way is a loggin tool, that writes the data the vertices move directly from 3ds or some other animation software, where you create the new animation with a new model. and this data is placed into the old "coordinates" from the former model animation, like dropping content into a container.
cant help more on this, im sorry.
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