There is a bug in AppSketcher's RoundButton_addOn.cpp file.
In the ArchiveRoundButton function the following lines:

	const rgb_color color = button->ButtonColor();
	archive->AddData("View Color",B_RGB_COLOR_TYPE,(const void *)(&color),sizeof(rgb_color));

add your changes to the BMessage's Data array of B_RGB_COLOR_TYPEs, but do not change
the first member of that array, so you won't see your changes when you reopen your Module.
You should replace the above lines with:

	const rgb_color color = button->ButtonColor();
	if (archive->HasData("View Color",B_RGB_COLOR_TYPE)) {
		archive->ReplaceData("View Color",B_RGB_COLOR_TYPE,(void *)(&color),sizeof(rgb_color));
	}
	else {
		archive->AddData("View Color",B_RGB_COLOR_TYPE,(const void *)(&color),sizeof(rgb_color));
	}
