Extract the file from the first link and run the "setup.bat" script. You can select "Install" to add the Unlocker to Origin or EA Desktop and "Uninstall" to remove it.
Then open the second link and read the tutorial on how to add all language files to your game and how to change the language.
Bump. Updated the tool to work with EA Desktop too. Installation is much simpler now, the "setup.bat" script does everything for you. But if you want to do it manually then first make sure Origin/EA Desktop is not running (open task manager and end all "Origin*" and "EA*" processes) and then add/remove the "version.dll" file for your client from the archive.