This gtk thing is always a little annoying. In 1.8 series it was just plain broken upstream, and by 2.0 it now needs a ruby gem. But in principle if you get the ruby gnome package it should work. However, it shouldn't actually be preventing lich from runnning, so there must be a deeper issue. (It just prevents narost from working in my experience.)

SystemRescueCD is a pretty good live distro I use a lot, though I've never run it from a USB stick. But it's gentoo based so I could at least help you debug better.

Translation: Sorry I've nothing helpful to add at this time.