Hi,
I love this module. But I have some promble and need some help.
I install as "Advanced Install", I put below code into settings.php.

include_once('./sites/all/modules/fast_404/fast_404.inc');
$conf['fast_404_exts'] = '/^(?!robots).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
$conf['fast_404_allow_anon_imagecache'] = FALSE;
$conf['fast_404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
$conf['fast_404_path_check'] = TRUE;
$conf['fast_404_url_whitelisting'] = TRUE;
$conf['fast_404_whitelist'] = array('index.php', 'rss.xml', 'install.php', 'cron.php', 'update.php', 'xmlrpc.php', 'authcache.php');
$conf['fast_404_string_whitelisting'] = array('cdn/farfuture', '/advagg_', '/devel_themer');
$conf['fast_404_HTML_error_all_paths'] = FALSE;
fast_404_ext_check();
fast_404_path_check();

At last it turn out a 404 error about authcache. And also Devel Themer have the same error.
I don't know how to start to fix this, can you tell me any clue?
Only local images are allowed.
Thanks a lot.