Installation :

[0] First Reinstall Atlantis The Lost Tales (in english language) from GOG Galaxy [1] Unzip AtlantisExtendedCutForGOG_ENG.ZIP [2] Launch AtlantisExtendedCutForGOG_ENG.exe (run it as Administrator !) [3] You can see the current directory of the game (Normally you don't need to change it) [4] Delete all your saves, just click on "Delete all save files" [5] Click on "Update to Extended's Cut Edition" [5] Launch the game from the updater or with GOG Galaxy