I'm using Kubuntu 12.04 with KDE 4.10, and I recently installed the
kde-config-grub2 that places a nice Grub configuration panel into KDE System Settings.
I played around a bit, more for learning how it works than for real necessity, since I don't really need to change its default behavior.
Everything seems to work as expected, the changes made here usually are properly set up and are shown at the subsequent Grub instance; anyway, in the appearance tab, changing the default colors, don't change the colors displayed actually in the Grub. I.e., I tried to change the default "light grey" to "light green" for text color, and after applying the settings in the tab, the grub still has grey text.
Every other setting works as expected, i.e. I can successfully set a background image, change the resolution, select default OS, default waiting time for autoboot, and so on.
Now, I don't really need to have colored text, like I said I'm most interested in this for learning purposes, but it will be nice to know the reasons of this issue.