Thanks, after your previous response I tried again. This time I displayed the listbox and saw the colors.
The documentation does not say what the colors are for and I think it would be reasonable for them to affect the installer colors and not just a list box which may or may not be displayed... For what the command does "ListBoxColors" would have been more appropriate.
Anyway I'm picked a better color, I know what it does and now I'm happy :-)
Of course if I real "InstallColors" comes along I'll try it out also.
I could make one small point here, I think that rather than have new commands for all of these types of things (particularly commands whose placement is restricted, I think it would be better to have variables such as perhaps
"$ListBoxBg" and "$ListBoxFg" etc.