1: sky: lose that sh*tty archicad background and get a nice graduated background - render sky with Lightworks not internal.
1A: reflections - go to lwa and get a higher reflective glass. or tune it up yourself.
2: exterior sun - combine weak built-in lightworks sun with .5 degree divergent sun object. yellow-ish more ambient and sky - bluish - every scene is different.
3: grass: keep working with pattern overlays on a darker, greyer green
4: I use Poser and OnyxTreepro, and the photo figures, too, but with blurring and reduction of contrast to match the ArchiCAD model - espcially attentive to sun angle.
5: If you mean overlapping planks like those white hip roofed houses along the road, it is overlapping roof planks. How hard can that be?
6: Want to see a citroen float - like a butterfly - and sting like a bee? go to:
http://www.theembassyvfx.com/main.html
portfolio - second from left - citroen ad. 6.0 mg clip - worth the wait.
7: there is no seven.
Dwight Atkinson