That bug has been described on https://launchpad.net/distros/ubuntu/+source/file-roller/+bug/40899

"try to make an iso file (just try with a small directory):

if you open it with file-roller and hit extract everything is correctly extracted

but if you click (in nautilus) extract here, from the rightclick menu only a directory is created, with nothing inside
...
confirmed in dapper
...


This might be of help to anybody trying to fix this:

pandis@maxwell:~/new/file-roller-2.14.2/src$ ./file-roller --extract-to=~/holmesnew/ ~/holmes.iso
ListExtractExtract
(file-roller:11343): GLib-GObject-WARNING **: invalid uninstantiatable type `(null)' in cast to `GtkStatusbar'

(file-roller:11343): Gtk-CRITICAL **: gtk_statusbar_push: assertion `GTK_IS_STATUSBAR (statusbar)' failed

(file-roller:11343): Gtk-CRITICAL **: gtk_widget_hide: assertion `GTK_IS_WIDGET (widget)' failed

(file-roller:11343): GLib-GObject-WARNING **: invalid uninstantiatable type `(null)' in cast to `GtkProgressBar'

(file-roller:11343): Gtk-CRITICAL **: gtk_progress_bar_set_fraction: assertion `GTK_IS_PROGRESS_BAR (pbar)' failed

(file-roller:11343): GLib-GObject-WARNING **: invalid uninstantiatable type `(null)' in cast to `GtkStatusbar'

(file-roller:11343): Gtk-CRITICAL **: gtk_statusbar_pop: assertion `GTK_IS_STATUSBAR (statusbar)' failed

(file-roller:11343): Gtk-CRITICAL **: gtk_widget_hide: assertion `GTK_IS_WIDGET (widget)' failed

(file-roller:11343): GLib-GObject-WARNING **: invalid uninstantiatable type `(null)' in cast to `GtkStatusbar'

(file-roller:11343): Gtk-CRITICAL **: gtk_statusbar_push: assertion `GTK_IS_STATUSBAR (statusbar)'"