To download a game you first need to login in the Member's Area.
https://www.matrixgames.com/login
Login and then click "MY PAGE" and you'll see the list of your registered games.
Find the game you wish to download and click "FILE DOWNLOADS" (1).
If you have not registered your game click the "REGISTER SERIAL" link (4), and follow the instructions to register your key.
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Click the Download button for downloading the installer(2), the update (3) or any other file.
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(*) Download server location.
(**) Number of users downloading the file / Max number of users permitted by the server