You can do it by drawing a map of walls and other object with wich the player can colide. Put that as an animation of a new actor, place it over your background so the walls match and put physical reponce with player on it. Now make it invisible and it will look like he is colliding with the walls.
You can also do it by making many fiiled regions to represent the walls but that would take to many actors.
BTW please use the edit post button when you make a mistake
