Well, I'll try.

Question 3). Open terrain editor and click on the small notebook-like icon in the upper right corner of the terrain preview. You'll get clipping brackets etc.

Closer etc. I don't exactly understand. Why don't you move it in X/Z/Y axis? Just the light?

Glaring Yellow. Play with Diffusion and Ambience in the Material Editor. The blue dots must be right beside the names of the categories, not in one of the texture places to the right. See the picture.

-- erlik