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The ES games series is a platform for launching games from steam but not using steam... That being said you are here for the achievements right? All you need do is launch the platform (game)... Don't bother messing around with adding the games into it; but rather just close the application. All the achievements it can give you will appear AFTER you close the game weather you added / played anything or not. The easiest complete 100% you have had in a while to be sure. Do check back as it seems as they add new content, they add achievements. Just repeat the open / close procedure to get new ones.