Shem is right, you have to select new game to play any DLC. This does not mean that you will have to play the entire game, just the new level you downloaded. This was the method established by the game producers to access the DLC levels.
Sh‚sotjontŻ ch‚tsatul nu tyŻk.
TyŻkjontŻ ch‚tsatul nu midwan.
MidwanjontŻ ch‚tsatul nu asha.
AshajontŻ kotswinot itsu nuyak.
Wonoksh Qy‚sik nun.