It sounds, to me, like you made the animation within the symbol itself. (I just tested it and it behaved just as you said.) If this had of been Flash, you would have been fine. But it's not, so we got issues!
IF this is what you did, you should be able to right-click on the ball in the first frame and under the Symbol menu, hit Break Apart.
As for running slow... That tends to happen within fireworks with large animations. Once you export the final product, that should run just fine. Well, as fine as a large animation can.