I had fun with it today. There is little problem with this script in GIMP 2.8.2, though.
Script crashes when # of Cycles is set to more than 27 (from 27 to 50).
I'm gonna give it a go with earlier versions of GIMP on Linux and Windows later on this week to see how it works.
Thanks for sharing your script here! There is a typo in script title (ration).