In the 'settings backend' it states... Send email to admin before Lend end.
However this is difficult to understand and setup so as to function properly. Please include clear instructions on this section.
ie:
Send email to admin before Lend end.
For that you need create GRON job and connect to Cron check so URL:
'http://{yours site}/index.php?option=com_booklibrary&Itemid={Yours ItemID}&task=lend_before_end_notify' with span - every day.
Cron Jobs may look like:
'wget -q -O -
localhost/~andrew/joomla_15/index.php?option=com_booklibrary&Iteid=56&task=lend_before_end_notify /dev/null'