Access to all tracks without Gold medals:
Note: This procedure involves changing a game file;
create a backup copy of the file before proceeding. Locate the
track you would like to play, but is locked (for example, "\TrackMania
Copy it to the directory "\TrackMania Sunrise\GameData\Tracks\Challenges\Downloaded".
Start the game and go to solo/single challenges. The map "Downloaded"
will now contain the copied track, which now can be played without
the Gold medal requirement.