Cheat codes enabled and most work (Windows 8 PC), but "Treasure Chest" for more debens does not yield more debens in the treasury. Does anyone know how to solve this?

(Note: didn't mean to put "treasury" instead of "treasure" in subject.)

You won't get more money when you have more than 5000 db in your treasury. Using cheats will invalidate your score immediately, and you won't have a record on the list for it.

If you are resorting to cheats to win a mission, you are probably not playing the mission the way that it was intended to be played in any case, or if this is in early tutorial missions, you aren't focusing on the tutorial goals to win.