I have two lighting mods and I like how bright the ground is in one of the lighitng mods. Which settings affect the ground exactly?

Is it:

World Data-Climate-Ambient lighting on the Z-axis?

that lighting template's or cell lighting's ambient -z value

The X Y Z of ambient lighting controls the direction ambient lighting comes from. The Z value controls its vertical approach, like the pitch on an airplane.

FYI if you turn on Sky lighting (little cloud icon on top row of buttons) you can change these values, hit apply, and see the change take effect in world instantly in the CK's render window. This makes it very easily to experiment with values.

By hit "apply", do you mean hit "ok"? Do I have to load a world space first? If so, how?

Thank you all so much for helping.

Oops, yes there might not be an apply button in that window. See tutorials in other thread for basics, as you have.