galternatives fails to work? The application window opens but you’re unable to make any changes? Perhaps you’re seeing errors like sh: 1: /usr/sbin/update-alternatives: not found?
The galternatives package in Ubuntu 14.04 (Trusty Tahr) suffers from a fatal flaw. It calls a hardcoded path to update-alternatives which does not exist. This is mostly the fault of dpkg, as it failed to include a symlink to update-alternatives in /usr/sbin as it had done in previous releases. Unfortunately galternatives did not help matters by referencing a symlink instead of a canonical path.
Luckily, this appears to have been fixed in future releases. In the meantime, there is an easy fix:
sudo ln -s ../bin/update-alternatives /usr/sbin/