Creating a MASK layer above an image can allow you to create transparency around the part of the image you really want to keep
Place an image on the stage and name the layer appropriately (ie "Image")
Create a new layer above the image layer, and call it "Mask"
Draw a shape (like a circle for a soccer ball) in the mask layer over the part of the image you want to stay opaque
RIGHT mouseclick the MASK layer and select the MASK toggle
Your image should now show through as defined by the mask layer
Note that both layers are now "locked" together. You can still edit either the layer, but you'll have to unlock them. They must be locked again to impose the mask.
A motion guide can act like a "rail" or train track that your tweened symbol has to follow
Place the soccer ball on it's own layer in front of a background layer
RIGHT mouseclick the ball layer and ADD A CLASSIC MOTION GUIDE
Draw a simple line on the guide layer that passes through the reference (rotation) point of the symbol and goes off into the distance
You can curve the line if you'd like
Tween the object so that it moves to another point on the motion path. As long as the reference point starts on the "rail", the tweened object should follow the path
RULES
The guideline MUST be intact in the proper guide layer, and NOT grouped
(be careful that the layer is a TRUE Guide Layer - it should have an icon of an arc - not a ruler)
The tween MUST start and finish on the rails
The line must be fairly simple, with no intersections or criss crosses
(be careful that there aren't any breaks, or extra lines at the old intersection points)
The Bouncing Ball Exercise
The objective is to make illustrated objects of various density appear to move believably on the screen.
Create a symbol from a bitmap using masks
Create classic tween motion to have the object move across the stage
Add a classic motion guide and modify the motion to make the object bounce