Need some help with druid skins

[Surikat]

Heya guys, I need some help with changing my druid skins, I´m really fed up with my tauren moonkin and catform models, I would really love to have them changed to Tigon for catform, and the Shadowform aura attachted to me in Tauren form, instead of the moonkin model, if that is too complicated, I´d like Tree of Life, Alliance Moonkin or any other cool humanoid form for my tauren moonkin form.
I´ve downloaded skins and stuff, but they wont work, since I need to download the fix program, and use it instead of wow, but I can´t do that, since I have a mac, and .exe files can´t be opened on Mac OSX.
Is there any other way I can go around this problem?
Any help much appreciated.
Cheers
/Funkmeister