I downloaded the tablamg2altitudefs3.png file from the files section and noticed that some of the colors on adjacent "altitudes" were filled (at least partially) with the same (rbg) value. As in, if you use an "eyedropper" tool and select pixels on water 14 near the edge of it's "square" it will be the correct color, but nearer to the actual number the color is the same as 16.
Anyhow, I didn't want people to be scratching their heads wondering why things may have come out strange (having accidentally clicked the wrong portion of a color "square,") so I filled in the problem areas with the correct colors. Here is the (hopefully) correct swatch.
Hope this helps!