These section allows you to customize the colors used within KMyMoney. If Custom colors is not checked, then default colors will be used.
To customize colors check the box Custom colors.
Modify any of the colors by clicking on the color button, which will open color select palette. This will provide unlimited options in color selection. You can select a defined basic color, pick a color by clicking anywhere on the screen, input an HTML defined color, specify values for Hue, Saturation, Value, Red, Green, and Blue.