I know at least five different ways to make platform game engine it depends what you want from game will it be like Mario free running game or game where you control ball which can bounce The main is idea of original game and after that you start thinking about actionscript
By the way you can invent your own original code for such type of games just google and find some books about actionscrip I reccomend reading them to not just copy from tutorial but understand how your game works
