Problems Importing Lerpz to 3ds Max

When I import the 3D platform tutorial Lerpz FBX to Max it comes in looking fine, but there are thousands of keyframe animations – to the point where I can’t easily modify them (Max starts to lag badly). Moreover, the animations don’t correspond to those in Unity. For example, in Unity, frame 1-33 is walk, 41-57 is run, etc. But in Max they are quite different.

My guess is that when Lerpz was exported to FBX originally, the real keyframes got chopped up indiscriminately. Is there a way to get the original keyframes? Perhaps something in the FBX import settings? Or, better yet, is there an original 3dsmax file available somewhere that I can download? Alternatively, is there a way I can add more animations to Lerpz without editing the FBX?

it may be easier to give him a new skeleton bip or cat if you have it. an animate however you like

Well, I was hoping to avoid that. I really wanted to get comfortable with Lerpz before moving on to a custom rig with my own animations.