Coyote

Hi! So, I decided to dive in on my own little worldbuilding and came to a halt with texture application. I want to draw a scar on my characters face and through WoWModelViewer I exported the .obj and all following files (texture png) and after editing the png how do I apply it on a model in WMV? After testing it there I'd export it and import it into blender I am new to this and if this is a wrong place to ask this question, could you point me where to go. Thank you!