Modifying CAF Animations

[MissingAFew]

We currently have the models and animations sold on vizard website and would like to modify animations in 3DS max (for example, take the animation in which the avatar falls and add a bit more so he gets back up).

Basically, we need to modify the animations given to us... not make new ones. I'm assuming this is possible since we payed for the for the entire package and received the models/rig. However I've only seen information on how to export animations, not how to import animations into 3DS max. Any help or direction would be appreciate, I've never really used .CAF before so I'm not sure how it works.