I'm having the same issue using the Majora's Mask texture pack. It needs the most updated minecraft, but on Tekkit it runs 1.5.1 and i can't figure out how to update the version it's using. You might be having the same issue, because so far it looks like only Minecraft itself is running 1.7.2, so if you can figure out how to update on the mods, maybe that will work? And if you do, could you please let me know? I really want to play with the textures as well on the cool mods!!