You can award points by simply filling in the fields "Points for buy-in", "Points for hit", "Points for rebuy", and/or "Points for add-on". The "Points for Playing" field is intended to provide a way to award points that require more complex analysis. Regardless, they all end up in the same place, the player's Points field.
Once your tournament is over, you should see values in the Points column on the Players tab. If so, then the formulas discussed should work when applied appropriately on the Stats tab, providing you've saved your tournament(s), the players in the tournament(s) are also in the database, and the Stats is configured to look in the correct place to find your saved tournaments. That is currently configured on the Preferences tab (but will change in the next version to be a bit more intuitive). Once you've run Stats (i.e., pressed the "Refresh Tourneys" button on the Stats tab), press the Info button to see which tournament files were found and filtered.