The most requested feature of the Cellgraph is now in operation: Colors.

I added one panel with all the options and functions to control them. It is a little complex, but well documented (see here). In short you can load and save from and to the config file single colors and color sets under special names. And then you have direct access to the gradient and the complimentary function of Graphics::Toolkit::Color. Reverting to the default grayscale is always possible with an push on a button.