You can drag the parts around by the black "control" dot. This is the Hue, Saturation, Lightness color selector. You can pick a circle in the palette to assign the currently selected color. Press 'C' to clear the current palette code. Press 'P' to show/hide the palette RGB codes. If you can figure out the ConfigData list you can change the bar height, palette circle size and some other minor settings.
I was needing a color/palette tool for a possible new project. This is just a front end change to the @TheLogFather and @DadOfMrLog projects listed below. Experimenting with storing variable data in a "ConfigData" list instead of individual fields, but I'm not sure if I like it or not. Possible future enhancements? - Add a configuration setting to use RGB sliders instead of HSL - Add the ability to import/export palettes - Allow 2 rows of palette colors - Allow the palette colors to be stored as HSL, RGB Hex, or the long RGB color number.