I am looking to register a reference to the main Database Adapter in the Registry during Bootstrapping so it can be used elsewhere in my site (specifically the Authorisation
Check the zend-documentation at : 15.5.3.3. Storing a Database Adapter in the Registry
http://framework.zend.com/manual/en/zend.db.table.html
$db = Zend_Db::factory('PDO_MYSQL', $options);
Zend_Registry::set('my_db', $db);
// Later...
$table = new Bugs(array('db' => 'my_db'));
something like that you're looking for?
Edit:
to load your configuration from an ini-file, use:
parse_ini_file($inifile)
;configuration.ini
host = 127.0.0.1
user = username
password = blabla
;yourfile.php
$options = parse_ini_file('configuration.ini');
$db = Zend_Db::factory('PDO_MYSQL', $options);