Okay just fixed it.
You probably used the wrong path..
Textures\heromountainking.blp
Anyway I had to make a new skin of the mountain king, but it works now.
Hope that's okay :P
EDIT
Here's just a preview to show that the skin works ingame..
Now give me a reward

Btw dude, why did you make the eyes in a part where his eyebrowns should be :?