Apple Motion 4 - Manual (Page 366)

Note: Cameras and lights that have been saved to the Library can be dragged to the
Timeline.
Dragging to a group track Dragging within an object track
If you are dropping multiple objects, you can choose Composite or Sequential from the
drop menu. Sequential imports objects one after the other.
Note: If you release the mouse button before the drop menu appears, the default choice
of Composite is applied. This means that the new layer appears on top of other objects
in the Canvas.
Composite
When you choose Composite from the drop menu, the new object is added to a new
track within the active group and all layers remain onscreen simultaneously.
Before After
To composite an object
1 Drag an object from the Library or Media tab into the Timeline tracks area.
As you drag, a tooltip appears at the pointer to tell you the frame number at which you
are located.
2 When you reach the frame where you want the new layer to start, position the pointer
over the layer you want as the background, and hold down the mouse button until the
drop menu appears.
3 Choose Composite from the drop menu.
The new layer is composited into the project.
366 Chapter 8 Using the Timeline