[Exitilus]

Yes. The plugin is very simple. all it includes is

if ($vbulletin->options['storecssasfile']) 
{ 
    $style['css'] = str_replace('clientscript', "{$vbulletin->options['bburl']}/clientscript", $style['css']); 
}

So all it does is add your BB URL that is setup in AdminCP. So if it's picking the wrong URL my guess is thats the problem. But you could replace the {$vbulletin->options['bburl']} with your forum url