1) it's called "updating"
2) just back up your saves, though in my experience (and plenty of others, from what I've heard) it keeps them anyway, probably has a separate save folder from the game files one
3) given how much time you insinuate you invested in this game, you enjoyed it, yet you're angry at a guy that all by his lonesome is doing every goddamn task involved in creating and updating an experience you, again, enjoyed, ALL. FOR. FREE.