The amazing BG - by tetrasnake. But I had to crop the image dramatically to obtain high enough horizon line. Then I blew up the small remaining BG image and applied noise removal in PS. Then went the first render with a white floor plane and with the invisible G2F (but she could cast shadows). The obtained shadows were applied to the BG (second layer in PS, mode - multiply), then shadow color correction was performed to get the perfect match with the colors of the real shadows of the photo. The created BG was used for the final render (import from DS4.6 into C4D - VRay render engine). The light - imitation of the reflected Sun light (from a window). And, of course, the Genesis 2 girl was surrounded by an invisible environment sphere (the same photo). Because human skin has certain reflectivity. And the sphere is used also by the Global Illumination. This way the skin and clothes of the girl get some tint from the street colors (so as to blend into the photo). Then, finally, some noise was applied to the whole image. I put such a long text here as a short tutorial - it seems that even my very talented friends may find something useful :-). Almost forgot - thanks for looking :-).