Its not actually a free game so if you are getting it for free then its a pirated content so don't expect the game you are downloading without any hooks and since it's an online multiplier game the game will stop at any moment when you download from working links.
I know its paid and that's the reason i am asking for any antithetic link to download and let children play it for free. There are DVDs of this game available in the offline market but usually some files are missing in those dvds making it impossible to install.