I've been doing this for a while and thought I'd share the idea. I, as a colourblind artist, am eternally grateful for the Presets and to that end have found that on the Grass Clump in particular which loads sans texture, if you go to the Colour Tab and insert the grass layers.tgc from the Presets pack in the Tint diffuse colour slot and leave at 1 gives you nicely varied grass, a blend of healthy and dry...plus as they are PFs are infinitely adjustable...have fun.