There are a few other fire shaders out there. A bunch came with P6 (can't remember if they were in P5, but I don't think they were in P7). RDNA had a freebie that might still be available. I haven't tried using any of these, so I'm not sure how well they'll look on a figure. A nice ember texture is available for the DAZ Troll, but you're not looking for that specifically--it might give you some tips for applying glow effects because it has a cool magma look.

My visual indexes of Poser content are at http://www.sharecg.com/pf/rgagnon