Hi Larry,
Could you please describe in a more detailed way how you went about to get the numbers you got? How did you physically position your eyes relative to the screen center and relative to the screen plane? I wouldn’t expect you to get any values at all if you position your head and eyes at the level of of the bottom border of the screen since that would be below the track box of the eye tracker – the eye tracker would not be able to find your eyes at that angle. For more information about the coordinate system used for the Eye Position stream, see the Developer’s Guide included in the SDK.