(Ohki)

Quote - Problem with that method is that it will only work nicely with a ball or other simple mesh, so I'd be interested if somebody could explain to me that atmosphere trick!

The atmosphere would be just as limited -if it were able to use a point light at all- and take much longer to render.  You can get a Godray effect around a doll using a spot light, but not an aura.

However, I have an idea that should work if you are doing a still image (as opposed to animation).    Get your scene set up.  render a silhouette of only the doll (or whatever needs an aura).  In your photo program, make the white silhouette an object.  Duplicate the silhouette object, and reduce it in size somewhat.  Invert its color to black, and overlay it on top of the larger white silhouette.  You should now a black shape in the center, outlined/surrounded by a white shape, on a black background.  Give the silhouette objects a shadow to soften the edges.  Now use this image as a transparency map for a billboard placed/scaled to fit the doll, and give it a generous ambient value.

I don't have time right now to screenshot a demo, as I have to leave and go on duty shortly.

For those who can model, you could "shrinkwrap" the doll (hair, clothes, weapons, and all), scale the shrinkwrap up a bit, and use that mesh as the duouble edge blend aura.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5