Managing actions

Hello, I have some troubles with blender action system…

  1. I can’t understand difference betwen actions, NLA strips and NLA stash

  2. Then, why some of my garbage actions (that I try to remove) has a “ghost user” (not the fake user)?

  3. I have a “run” animation linked to the fake user and to a (again) ghost user, but it seem that animation has been created with this “ghost user” because when I select my armature I can’t see any keyframe on the dope sheet in contrary of the other actions. Yet this animation make my character move.

Here’s the .blend
character14.blend (912 KB)

Thanks for your help

May be you want to read this https://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.74/Animation and this one as well http://aligorith.blogspot.fi/2015/06/blender-animation-faqs-june-2015-edition.html