Just unpack and start the new version. Keep your old ones too, they have unique secrets and content! The game stores all its saves and assets in a different location than the folder the game comes in, so you don't have to worry, just don't start saves from newer version in old versions; if you want to back up your settings and saves and such you can access the game's universally stored files by going to settings and looking for the option to open the assets folder
