This flame effect is generated on-the-fly using bitmap effects.

What the source includes: caurina (library), source.fla, preview.swf

Caurina is a library which includes the Tweener class. I use it instead of the standard Tween because of its ease of use. I am not the creator of this, and it is publicly available elsewhere. I strongly recommend using it.

dynamicflame.fla
This is a watered down version of the preview file. It only includes code relevant to the flame effect and does not include the buttons and checkbox features.

preview.swf
This is the preview used on BuyStockFlash. I will not include the source for the preview file. You are buying the flame effect and only the flame effect. If you want more, show your interest by asking.