Sure. Itachi's saving of Sasuke was a crucial moment in the manga. It was tied to his hidden motives and sacrifices for the greater good of the ninja world and Sasuke's future.
You can't do that. Manga Rock is not a legitimate source for saving chapters. To enjoy manga legally and ethically, look for official and licensed services.
Well, if you don't save the data, you risk losing everything you've done. Maybe you spent hours on a detailed drawing or an elaborate storyboard. Not saving could mean starting from scratch, which is a total bummer.
It depends on the version of Manga Studio you're using. Some versions have an undo function accessible through the toolbar or Edit menu. But if it's an older version or if there were certain settings changed, it might not be possible.
Well, sometimes it might involve a heroic sacrifice or a selfless act of love. That could be the key to saving a soul splitter. Also, finding a hidden artifact or relic with special powers could be another option.