Cool stuff CR. Must have taken a long time to enter all those map coordinates. Impressive.
I did something very similar back in July of last year, and added it to my v5 board. I took a slightly different approach, inspired by the RGB spectrum color picker used in some graphic apps.
Here's the output of the perl script that generates the colortable gif and the image map code.
Here's a zip with the source. The parameters are hard coded, but it did what I needed at the time.
You can see the color picker in action by visiting
my UBB . Sorry guys and gals, it's still a v5 board. I promise to upgrade "Real Soon Now"®.