There's a new version of gonvert available at the URL. It works fine with the 0.2.12 ebuild. I had to mv 0.2.12-about.patch 0.2.14-about.patch, though.
0.2.15 has been released some hours ago. Included fix: When starting pre-0.2.15, the following message showed up: /usr/bin/gonvert:2983: GtkDeprecationWarning: gtk.mainloop is deprecated, use gtk.main instead gtk.mainloop() That's been fixed in 0.2.15.
Bumped.