City living pack not showing up

I was wondering if anybody knows why the City Living pack I just downloaded is not working at all? The world isn't even showing up. I think it has something to do with my mods because when I turn them off It shows up, but I can't figure out what mod it is. Does anyone know the easiest way to figure out broken ones as I have so many mods to sort through! Ive been trying to get it to work for days.