Please add to the documentation that after upgrade of database / mail / web server packages to make sure that LC was restarted afterwards.
I did a apt-get upgrade and LC, apache and mysql were upgraded in that order. LC did restart but it was before apache and mysql were upgraded. I did not realise this and database and web server became unavailable in LC. To be sure I did the manual restart with liveconfig -k and then it worked again.
Beside documentation, it would be interesting when LC could detect itself if there was an upgrade of software and just reload the necessary data.