Hi! On some servers different css and javascript load mode is necessary, so you could try to go to the WordPress’ left menu Settings -> Nextend Settings, and try to change it.
You could try to change the cache folder too, because if the current one isn’t writeable by php, then our files weren’t created, but this usually solves it.
But it could be, that there is some javascript error, what you can check, if you would install Firebug in your Firefox browser, press F12 on that page, where this error is, then click on Console, and refresh the page.
Or a problem could happen with our menu, if in the html code there is a bigger error, like the </head> or </body> </html> is missing.
If these won’t help, then please send me a link to your website to my email address: [email protected]
