Since there have been no changes in the database between 1.9.6 and 1.9.12 you can simply put the 1.9.6 php files into a second directory and copy over your ost-config.php + language + plugins. Then you can access osticket from 1.9.12 and 1.9.6 and see if the issues are then still there or gone (when using 1.9.6).To further troubleshoot you may want to check the logs (osTicket, webserver, php) then and see if there are any obvious errors / warnings between 1.9.6 and 1.9.12.