Rombo materials come with automatic MILA light paths support.
All you have to do is to enable them under Settings->Scene->Camera->MILALightPath.
Here for example I enabled diffuse direct and indirect passes together with glossy reflection pass.
This is the full beauty output (gamma corrected).
These are instead the various pass outputs. Diffuse direct, diffuse indirect and reflection respectively. We don’t distiguish between indirect and direct reflections for the moment, so just enable ‘Direct Glossy Specular’ to have both in the same pass.
Once passes are composited together, they will return the un-gamma’ed (never compose in gamma space) linear beauty output above.
Same goes for rombo.skin for example where we have to enable the ‘front scatter’ MILA pass where we’ll end up having our SSS contribution.
Diffuse contribution (barely seen)
Reflection contribution (yep it’s there)
That once they are composited one over the other will get back this result (that has been gamma’ed).
If you plan to use passes with progressive mode be sure to have at least version 18.104.22.168 (end of april 2017 release).