First let me mention, that these presets are designed to be quickly tweaked by users. Used maps for Forest Color
- Get Color from Map
can be replaced by any other to easily get desired look.
As it might be a Forest Color
compatibility related issue, would you mind to specify used Forest Pack / 3ds Max / renderer versions? Thanks in advance.
Let me add, that depending on your scene (lightning / rendering) set-up the difference between light / dark presets might be not so visible as on thumbnails. Please feel free to add a Color Correction
map just before the Forest Color
map as shown below to fine tune the overall look (exaggerate brightness for example).