So I'm terrible with nifskope but I'm reasonably sure I can follow instructions.

https://www.youtube.com/watch?v=eZ9ZUN4BFvg

^I did this tutorial to make a custom mount. I followed the instructions explicitly. However, in game, my character gets onto the back of the mount, and then I can control the mount but the player avatar stays behind. I've rechecked my work, and I don't see what is going on. Here is a link to my edited skeleton:

http://www.mediafire.com/download/ky9j4lentowv900/skeletonReindeerMount.nif

I must have missed something.. but I have no idea what. Can someone please check my work?

Any help anyone could provide would be super.