Creating a Game Menu and a Particles Effect: An Angry Birds-like Game, Part II - Learn GameSalad for iOS: Game Development for iPhone, iPad, and HTML5 - page 232

Figure 7-40. What content to display for Level box
Position three instances of the BoxLevel actor on the Menu scene, as per
Figure 7-41.
Figure 7-41. Positioning the boxes
Open each instance of the actor on the scene and change the level attribute
from one to three, starting from left to right.
Next, you will implement the sliding effect.