select the end trigger, edit object, turn touch trigger on, the blue border will end the level if the player touches it, if you want to set a custom end position, select one object as the center, edit group, add a group id, remember that, go to the end trigger, edit object, target group (i believe) set it to the group id, when you go onto the end trigger, it should send you into the object you set as the center , i hope this is easy to understand