Hello, I've searched for a few days on how to edit stock maps.  I've only been able to do small things like give zombies Richthofen's officer cap, and make them Verruckt sprinters, along with always sprinting from round 1. Simple silly things like that. But when it comes to editing and adding perks. Or revamping the map, I completely come to a stand-still and have no idea where to even start. I want to mess around with the stock maps and make fun stuff, is basically my  goal. Switching wall weapons on the maps and things like that, also changing zombie models to different ones through the files. If it's possible, all help is appreciated; thank you!