Just a small utility I’ve been using to make my life easier, a little addon that lets you assign names to layers in an armature and hide/unhide them in the 3D View Properties area. Download it here, unpack then install via the add-ons area in user preferences. Works on current SVN (and the soon-to-come beta hopefully)
There’s also a ‘hidden’ operator you can use in the 3d view (search for change bone name layer) that allows you to switch selected bones to a named layer.Â It’s a bit rough, but the panel at least beats having to hunt and peck one of those 32 nondescript little buttons 🙂
This isn’t really part of the gilgamesh rig, just a utility I’ve been using while rigging. The final UI (you can see a peak of it just under the layers in the screenie) has hardcoded layer names, and only those that are relevant to animation.