[ga2000gt]

the name of the hack is 'Improved Thread Preview', yes, it's the link i put above.
is only one plugin, then there are a few templeta changes and two js files.
hook location is 'threadbit_process'
i don't know how to check the 'execution-order', if you tell, i'll do it =P
here is the plugin code, maybe it helps...

if ($ignore["$thread[postuserid]"])
        {
                $thread['preview'] = '';
        }
        else if (isset($thread['preview']) AND $vbulletin->options['threadpreview'] > 0)
        {
                $thread['preview'] = strip_quotes($thread['preview']);
                $thread['preview'] = htmlspecialchars_uni(fetch_trimmed_title(strip_bbcode($thread['preview'], false, true), $vbulletin->options['threadpreview']));
//tc
                $thread['preview'] = preg_replace("/\n/\n","<br />",$thread['preview']);
                $thread['preview'] = str_replace("\r\n","<br />",$thread['preview']);
                $thread['preview'] = str_replace("\n","<br />",$thread['preview']);
                $thread['preview'] = str_replace("\r","<br />",$thread['preview']);
                $thread['preview'] = str_replace("--","- - ",$thread['preview']);
//tc
        }