Bouncing Ball with gravity? Switch animation?

[GameDevs]

I have two problems where i cannot get a ball to bounce around forever and like it has gravity. I use the built in movement pinball and when i have my events say " When object overlaps obstacle group: Ball bounces. "
My ball just bounces back and forth form where it came from and doesn't bounce forwards, it always reverses direction. Will a built in movement simulate and detect what it hits (like top of obstacle, side of obstacle, top of obstacle?

I also have another problem. When i try to change my animations on an active object it never does (or it seems to not do it). I have it when my object collides to change animation to stopped, and the stopped animation never plays.
Is thier a certain way to change animations? What if the animation goes out of bounds of the original? Would the size increase? Can the size of an active object be changed with code?

[GameDevs]

I wanted a bouncing thing like the mario star powerup....
Its very hard to simulate it by doing numerous checks (as it wont detect if you re landing on a surface, hitting one sideways, hitting one from underneath or other things....) and i wondered how to do it more efficiently or even just HOW....

[clean_citrus]

Like this?. I don't understand the problem with the pinball movement but I used it in the example and it seems to be what you're trying to do.

[clean_citrus]

By the way, the fact that the animations i used in my example are the same size doesn't matter. I could've made the hit animation something of a different size or shape and it would behave the same way.