The basic section of the multimedia data-processing system includes a CPU 1100, an image display unit 2100, a unified memory 1200, a system bus 1920, and devices 1300, 1400, and 1500 connected to the system bus. The structures are applicable, for example, to semiconductor interconnects, polysilicon gate, and capacitor applications. Cooperative interaction is facilitated over a wide variety of networks by messaging through a common API that supports multiple transport mechanisms. The assembly includes a plurality of adjustable length legs. Use of the optical path shifting unit reduces the height of an optical pickup apparatus, thereby providing a slim optical pickup apparatus using an existing light source and photodetector of a conventional size.