Boing??
Randy,
you would need to hold the ball still for the duration of the bounce.
This means you'll split your path in two: the path before the ball hits the
platform, and the path after. If your squash/stretch is 5 frames long,
leave 5 frames between the two separate "Position" tracks:
1 2
1234567890123456789012345
[=======================] Actor
[========] [========] Posn.
..
[===] F/X 1
I tried it, and it works fine.
Blaq!