if you are doing an animation with a person then be sure to import the skeleton and you don't need to use nifskope, just use the kf file
That comment is incomplete and won't help almost at all if one is going to make a character animation. The skeleton needs to be rigged and armed with meshes, and it must be "fixed" in Nifskope.
OPI have helped others (including myself, lol) to make character animations.
I collected here some threads about my current saldo of animation related stuff:
http://www.gamesas.com/index.php?/topic/1107622-edit-kf/
http://www.gamesas.com/index.php?/topic/1104171-little-animation-problem-d/
http://www.gamesas.com/index.php?/topic/1106522-need-help-moving-kf-and-associated-nif-around/
http://www.gamesas.com/index.php?/topic/1107225-stuck-with-blender/
http://www.gamesas.com/index.php?/topic/1107454-special-idle-misbehavior/
http://www.gamesas.com/index.php?/topic/1107750-splitting-appart-meshes/
http://www.gamesas.com/index.php?/topic/1107824-blender-question/
Read the whole topics, and try to "get it". Also, study the tutorials to which I gave links in the first link, and look for more. Don't be afraid to PM anyone that has experience with animations (probably all of us who have written in those topics).
EDIT: Of course; http://cs.elderscrolls.com/constwiki/index.php/Basic_Animation_Tutorial