Lux render using Luxus. not postwrk and not really what I wanted but it will do until I can learn more about LuxRender but to be honest I like the Octane DS4.5 plug-in better, or I should say I like the look of it better than Lux Render.
Now for the sharing bit.
Cube with Lux Volume added, set the Daz Studio surface to 10% Opacity, can be lower or higher, LuxRender surface to Opacity 0.10, Camera just outside the cube . Also I found the cube should just touch the outside of the window glass to avoid some nasty glow effects that I was getting on the outside of the glass. As soon as I changed the position of the cube the issue went way.
LuxRender Volume Type - Homogenous
Luxrender Volume – Absorption Colour -164,164,164
Luxrender Volume – Absorption Scale - 0.030
Luxrender Volume – Scattering Colour - 227,227,227
Luxrender Volume – Scattering Scale – 0.090
Luxrender Volume – Scattering AsymmetryR – 0.030
Luxrender Volume – Scattering AsymmetryG – 0.030
Luxrender Volume – Scattering AsymmetryB – 0.030
Sun/Sky and two plane mesh lights for fill.
Applied a little bloom and glare in the Luxrender UI
Click thumbnail to see full-size image