Saxon's (all credit to him) mod was incorrectly made and not maintained. He must have used a 7zip file and renamed the extention to .pk3 from .7z This is incorrect. You must take an existing .pk3 file, empty it and then mod it's insides as you desire or simply rename a zip file to pk3.
Just put it in the main folder.
ALL CREDIT TO SWAGGLETOOTH/SAXTON FOR MAKING THE MOD.
His Mod - Moddb.com
If you see this Saxton. I will take this down at your request and you can feel free to reupload it in your own account or whatever you wish to do with this.
Nice mod Saxon and thanks.