I left that out because it felt to me that many users can use the results screen differently (actual results, story,...). But the traditional one is easy: in the enemy object, in the destroy event, have some counter variable (held by the player or perhaps a global controller object) increase by 1. Same with treasure. Then you can use those values to draw text to your own results screen using the text functions of game maker.
This would probably have to be included in the save-load system as well, but only if you want these values to matter across stages (for some final score after a chapter for example).
As for controller support, eventually I will update this template further so I might include it (don't have much time right now though).