I'm not sure if this matches how the template does it, but I did it in PaperAirplane! by creating an attribute for each level as a numeric (or integer). When the level is completed, if the current value of the attribute is less than what the player got, I change the attribute's value to the new one. Then, on the menu, I have an actor with the image of a small star and use a repeat behavior in that actor to repeat the value of my level attribute, so on the menu it shows as the number of stars that the player acquired for each level.
So game.level1, game.level2, game.level3, etc. each have a value of 0 thru 3. Then there are star actors (instances) with a repeat behavior and the number of repeated elements is game.level1, game.level2, game.level3, etc. for each actor. It was a lot of work, so if the template does it easier then that might be the way to go, but this was what I came up with.
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So game.level1, game.level2, game.level3, etc. each have a value of 0 thru 3. Then there are star actors (instances) with a repeat behavior and the number of repeated elements is game.level1, game.level2, game.level3, etc. for each actor. It was a lot of work, so if the template does it easier then that might be the way to go, but this was what I came up with.
An example of it is in my game here: http://itunes.apple.com/us/app/paperairplane/id423266982?mt=8
Also, you can easily save the attributes each time they're changed, and load them when the game loads.