Need advice with GIMP

[Visaggio]

Hey folks, I'm looking for some help with GIMP. I've got a specific idea of what I want to do, just not sure how to do it.

I'm making a DnD encounter map for use with MapTool. An open grassy area with a few trees. (A small cabin and a couple of tents too, but i'm not there yet) I've made the trees, put in the trunks, now i'm trying to add some branches. (see Trappers Camp.jpg)

What i'm trying to do, is add the "flame" (Filters/Render/Nature/Flame..) centered in a circle, this will become my "Branches Mask" so that the Flame render with color can be set slightly transparent. I think this would make nice looking branches to finish off my trees.

I can't seem to get the "Flame" to render centered on my circle selection. I would like to get the "Flames" to radiate out from the center of my circle selection in such a way that i can use them as a mask.


P.S. I would like to send special thanks to RobA. Everything i know in GIMP i learned from his (Using GIMP to Create an Artistic Regional RPG Map) tutorial. Awesome work RobA