Hrqls: If everyone scores at least half of a point for each game win or lose, then why not score it 0 for a loss, .5 for a win, 1.5 for a gammon and 2.5 for a backgammon (or 0, 1, 3, 5 if you want to use whole numbers). Same, thing, yes?
Also, sadly, the tournament system here is not set up for the type of tournament you describe.