"First Light" is a Skysphere / Environment map addon for "Easy Environments: Tree of Life".
It works as stand-alone, you can use it with any environment you like, the main set is not required.
Compared to the "Tree of Life" skysphere, the sun is lower, giving the scene a red/orange tint, and the landscape is mildly changed.
The file formats are native .DUF for Daz Studio 3Delight and Iray, and .PP2 for Poser.
Lighting included for all versions (in case of Iray through the HDR environment).
You can get additional info and tips here: http://flipmode3d.com/easy-environments/