1). The Main and Aux cameras will always orbit the the zero point of the Poser UNIVERSE, unless they are parented to something, in which case their orbital focus (center) will move with the thing they are parented to.

2). The Figure Circle shows the Position of the BODY actor. The hip actor of a figure is parented to its BODY actor. By default a figure's hip in usually in the same location as its BODY when it it first loaded. If you translate the hip it moved away from the from the BODY Band its axis of rotation. Think of the BODY actor as an invisible prop, to which the hip is parented.

To move the hip back into the center of the BODY's figure circle, zero all the translations of the hip. To keep the hip in the canter of the figure circle, don't translate the hip in the x or z direction, move the figure in x or z by translating the BODY. The BODY's yTran should normally be kept at zero, and the figures altitude (only) set in the hip.