While doing scene setup, you can avoid lagging response from camera movements, etc, by changing to a simpler display style . Look for the pallette with these little "billiard ball" icons; The upper left (silhouette) is the simplest/fastest, and they get progressively more complex/slower as you go right/down. I use the fourth one, hidden line, a lot for setup work; it makes seeing poke-through easy and is good for getting things positioned. No.2, outline, is good for use with the front/side/top cameras to precisely position a point light within a candle, for instance. Once you're ready to apply materials, switch to No.12, texture shaded, to see how tiled materials fit to the model, etc.

Another way to speed up preview response is to change the tracking mode; fast tracking will show dolls/props as boxy robots during motion, then revert to full detail when the camera (or dolls) stop. These controls are at the bottom left of the document (preview) window:

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5