There must be something else going on because I’ve never had to do any of that to get a genesis theme installed. I’m not sure what you’re referring to by “live.css” since there is only a style.css file included in the child theme……unless you’re using something else to handle all of this. Whatever it is it’s definitely not normal from what it sounds like. You shouldn’t have to remove any files or code to install any themes.
Are you sure everything is working properly? Let me know if you want me to take a quick look.