the name "difficulty" mod is too general. there are many changes and some users might want one but not another.when you open the archive you can see new features named and seperated in folders. to install wanted feature you must extract folder content to "the witcher/data/".f.e. when you'll install leveling change, you'll get new files in "the witcher/data/utc/" folder. same way you should apply all wanted changes.if you like all changes, extract content of "all_in_one" folder to "the witcher/data" creating new folders like override, utc, uti, ... , etc in "data" folder.if you have further questions just ask.