Hi,
Unfortunately, MultiTexture (CG Source) / VRayMultiSubTex will not work as Distribution map in Forest Pack, because they are computed at render time, but scattering process is done in a previous stage.
Anyway, would you please post an example how the distribution should look like? Thanks in advance. I would suggest "baking" the map to texture, but maybe there will be another workaround ...
Kind regards,