Is there any way I can save the installer files locally (on my hard drive) so that, if I
reinstall Windows and I don't have internet, I could install and play the game directly,
on the same machine?
You can try this method: http://answers.ea.com/t5/Origin/HOW-TO-Backup-restore-Origin-games/td-p/3480967
It will probably not work to reinstall the game without Internet as the game will need to be reactivated on that computer.
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