I'm aware the game is advertised as a multiplayer game, but just checking, is it possible to play alone in the adventure mode?

I really love this game, but it is quite frustrating that you need to start over the whole world. So if you are in the iceworld on level four and you stop the game or even just missclick on 'menu' instead of resume after pausing you need to replay all the ice levels. Some auto/manual save or at least one of these 'unsaved progress will be lost do you want to leave..." messages would be great. ...

Is there a way to play online? Or will there be one in the future? I didn't see anything about it in the description.