Hi Benjamin,

I am really sorry for the delay of this reply.

I've checked your error log from your joomla site and it seems like you are hitting the following error when you trying to embed any link inside the story form:

PHP Fatal error:  Call to undefined function mb_detect_encoding() in....

This error will appear when you do not have Mbstring installed on your php server. You can refer to the following link here for more info about mbstring, http://www.php.net/manual/en/mbstring.installation.php . Unfortunately the only way to resolve this is by you contacting your webhosting service provider and ask them to enable php mbstring on your site.

Hope these help.