Various cheats:

Code                            Result 
siipiveikkoliitelee             Enable Hard Tracks 
lee Enable                      Hard Tracks 
hiihtoope                       Enable New Rider (Guide) 
ope Enable                      New Rider (Guide) 
imhotepmaailmojentuhoaja        Debug Mode (Press E During Game) 
seivaavideograbbi               Take a Photo 
exterminaattori                 Unknown 


Activate All Levels
First open up the /Saved_Data/ map in your "Supreme" folder.
Then open up "Avaiable_Levels.txt" and change the offsets to:

{
"Easy",1,
"Medium",1,
"Hard",1
}

Save and exit that file.
Then open up "Defaults.txt".
Change the line that says:

available_tracks = 3;
to
available_tracks = 7; 

Activate All Boards
     Go  to your directory where the game is and go to the folder \saved_data.
Open the file: Available_Boards.txt. Change what you find to this:

{
"Board_1",1,
"Board_2",1,
"Board_3",1,
"Board_4",1,
"Board_5",1,
"Board_8",1,
"Board_10",1,
"Board_11",1,
"Board_12",1,
"Board_13",1
}