Looking for model modification materials

[Lava495]

I'm working on an essay about game localization. I want to talk something about WOW, focusing on the model modification. An example of this is about the Undead in China.



Can someone provide any information about what Blizzard did to make it easy for local operator modify the models in WOW?

For example, as far as I know, the local operator can modify the models and pack them into a .MPQ file then players will download the .mpq and use it as a patch. Would anyone tell me how does .MPQ file work as an archive of compressed models and other things?

Thanks