How to make WOD models work in WoW Model Viewer?

[Flamy507]

I understand that old expansions were using MPQ files.
WOD uses CASC database or something in those lines

My question is how to exactly make it work in WoWModelViewer?
I lack basic knowledge when it comes to extracting files and saving them as something entirely different ;O

All I need is Gul'dan, Grommash and new Orc Models.

PS: I've read some posts here but they were quite unclear and made me pay for most of the software out there ;p