Error: Can´t access admin page

I had to change the plugin file to make it work. I think it can help someone and even the plugin’s author should consider making these changes.

on class-admin.php, create this function at the beggining (can be line 9):

function loadXmlByCurl($url){
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_HEADER, false);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    $xml = curl_exec($ch);
    curl_close($ch);
    $xml = new SimpleXMLElement($xml);
    return $xml;
}

Now replace this line:

$dom_object->load("http://www.facebook.com/translations/FacebookLocales.xml");

by

$xml = loadXmlByCurl("http://www.facebook.com/translations/FacebookLocales.xml");
 $dom_object = dom_import_simplexml($xml)->ownerDocument;

and you are ready to go