Flash plastic buttons - Page 15

Create a new layer.
Name: shadow.
Drag it below the others in the layers palette.
Again: delete the frame in the hit state on this new layer!
Lock the other two layers, because else it's almost impossible to work with your shadow. (Lock by clicking the lock on each of the other layers.)

Drag an instance of shadow from the Library on to the stage.
Centre it to stage by using the Align panel.

Now will adjust it's placement, to indicate light direction.
I use the arrow buttons to move it in place. I used 3 to the right, and 3 down for my example here.
Insert a keyframe in the Over state, and one in the Down state on the shadow layer.
I used the Advanced panel again. (In Properties Panel when the object's selected, choose Color drop down menu, Advanced.
Beneath are my settings.

Normal	Over	Down

Your button is now finished. As a pill shaped button.
Now it's up to you to add text and funny things happening to it...