Good luck! On the focal length thing, try the following experiment. Load a figure. Click on the Face Camera. The default is probably something like 25 or 38mm. Notice that the face seems to bulge, like a "fisheye" lens effect. Increase the focal length to about 100mm. Yes, you're now really in the model's face. But when you back the camera out along the z-axis, you will not have the "fisheye" look to the face. If you need to render at both settings to compare them side-by-side, do so and you will understand the effect focal length has on close-up portraiture.