Well, it's a Commodore 64 graphics editor, those colours are kept fixed because they fairly accurately represent the VIC-II colours, even if the palette is altered for personal taste.
It's especially important when using multi-colour mode and the 'Char' pen as the palette image then changes to indicate the "multi-colour" versions on the lower row (as seen in your image above).
ie. If you are using the app for non-C64 work then the concept of the Char pen having 8 hi-res + 8 multi-colours fails and a recoloured palette image would make no sense.
May I ask what platform you are pixelling for?
Trying to use it to edit for my own engine, with PNG output. I like the limits imparted by the structure of the C64 graphics setup, but I need to use a custom palette and not being able to see what color I'm selecting makes the custom palette really hard to use for anything other than variations of the C64 palette. Seems like a shame it's not easier to use for other environments.
