Der CC am Shop recht am Anfang hats eigentlich dann auch schon entschieden...

Sorry about that. I tried to be as clear as possible, but mankig games is inherently tricky.By the entire background object , I was just referring to the object we named back .The reason I am referring to it this way, is because the point of this tutorial is that we split the back object into multiple parts. Each part has a different function, but they are all still a part of the back object. We create a part inside the back object for the visuals, which has the important function of mankig the game look pretty, but we don't want the player to be able to collide with that part, or else he would be blocked by trees and grass in the background. So to fix this, we create another part inside the back object : the collisions part. In this part, we only draw lines that we want the player to collide with. This way, we can do a collision detection between the player, and back.collisions, and the game will run smoothly.I hope this helps clarify things! Let me know if you are still having trouble :-)Ben

That addsreses several of my concerns actually.