Musetup does it's job -- setting up the initial set of config options museekd needs set to be able to run -- but is quite limited... enter Musetup-GTK.
As a PyGTK app, it has a nice GTK2 interface.
At the current time, musetup-gtk is only for direct editing the XML config file of the MuseekDaemon (default: config.xml ).
You'll need to use it while museekd isn't running, or else your changes will be reverted if museekd changes anything. The changes won't take effect until you restart museekd, anyway
You may cancel your changes at any time by closing musetup-gtk without saving, or by (re)opening another config file.
If you want to see musetup-gtk in action : MusetupGtkScreenshots