Or what scitunes said but add an "every y seconds" timer inside the "after x seconds" that changes the color or transparency to fade it out before the destroy (place the destroy inside an "after x-1 seconds" timer). Or instead of the transparency, have an animation sequence of it shrinking/crumbling/whatever that plays and after the time the sequence needs to play once, destroy.
Comments
So I just gave him a little encouragement! ;-)
http://gamesalad.com/game/play/44115
http://gamesalad.com/forums/topic.php?id=4047#post-23952
In that case, you could have a rule like:
If platform collides with player AND player motion.linear.velocity.Y < 0 then break platform
http://gamesalad.com/game/play/44115
http://gamesalad.com/forums/topic.php?id=4047#post-23952