Hi Jean,
Alas, the installation and activation instructions appear to not be
applicable to Ubuntu 11.10, which doesn't have the range of choices in
> > Appearance that earlier versions did. I don't
know yet whether the function is hidden somewhere else, or if one
needs to install the Gnome Tweak Tool, or what one can do. I only
discovered this today and haven't seriously started researching the
matter.
It has been hidden, but apparently there is a way to get back some of the old functionality :
http://www.webupd8.org/2011/10/things-to-tweak-after-installing-ubuntu.html
Alex