How do I Create/Destroy sprites On/Off-Screen?

Hi.

For a few days I am trying to create sprites when another sprite is on-screen and destroy them when they are not on-screen, but with no luck.

I want to reproduce dust/steam effect and this is the method that works best as visuals in C2.

I reproduced a .capx with an example here:

dropbox.com/s/san0xtw2q5r285c/OnOffScreen_ObjectsCreationDestroy.capx

I have a sprite called "DustCreator" that spawns a few sprites for each image point it has and then apply some of its instance var values to the sprite effect that has created. But I want it to create those sprites when "DustCreator" is on-screen, when is not I want to destroy the sprites he created. This way I wont have a lot of sprites in the layout.

I hope I explained right.

Thanks you — , you saved me !