IMAGER uses a color scheme to highlight important messages. Two color models are available to maximize visibility on dark background (DARK model) or bright background (WHITE or LIGHT or BRIGHT model). Command SIC COLOR also to select the model, and a default can be placed in your $HOME/.gag.dico logical name definition file, e.g.
GAG_COLORS DARKDefining a text editor here may also be useful, e.g. for geany
GAG_EDIT $PATH_TO_GEANY/geany