This is a script that is based on the fire tutorial (http://gug.sunsite.dk/tutorials/tomcat13/). It was built and tested on GIMP 2.4 (so, using the new scheme engine).
It comes with two versions; one that creates an image of flames and another that creates an animation (using layers as frames).
Amazing Circle technique with advanced options. Includes options to choose border colour (or calculate from border average), border size and vignetting effect, whirl/pinch distortion, alternate circle method, plus optional drop shadow & shading.
After you download the script to your scripts folder and refresh your scripts (Filters -> Script-Fu –> Refresh Scripts), you'll find the new script in the menu under Script-Fu> Darla –> Saturation Fix.