[Request for Help] Editing model in Cinema 4d from animation set to then port into unity

Greetings, I am a complete beginner to both unity and c4d and trying to learn in spite of everything seeming quite overwhelming.

The project I'm trying to develop for educational purposes is the following:

Starting from this animation set: http://we.tl/kdfNegBQG6

( a screenshot to avoid the hassle of downloading http://i.imgur.com/GRPqyC3.png )

my goal is to replace the demon model with the body of a human and the wings of an angel, decreasing the size of the wings a lot, and all of this without losing the animations.

Now, my problem is that i don't understand at all the machinations of what is going on in this file, I have no familiarity with the terms rigging, skeleton, joint, IK?, baking, etc, much less being able to tell what the model in this file is classified as, if it was possible i would appreciate if someone could take a look at it and tell me the animation and rig system that exist in this file.

I would also like to know if it is possible to achieve my goal, if changing the size of the wings is possible without ruining the animations, and if it is possible to change the model.

If yes I would greatly appreciate being directed to an appropriate tutorial that could help me, I have tried to search but since I dont even know how to identify the animation type or the rig type it's been hard to find the information i need.

Thanks in advance.

 

Anyone?