Hi Swissvegan
Thanks for getting in contact with us. I see this issue on the link you have provided. Before we delve any deeper I’d like to know if there is anything specifically conflicting with the plugin. Therefore, would you be able to revert to a default template such as twenty-twelve and see if the issue is still occurring then. If that doesn’t seem to do anything, then try deactivating your plugins, one by one and see if any of them help with the issue. Once we’ve narrowed this down or isolated the issue, we’ll be able to give you a better idea on how to fix it.
Let us know when you do that and what the outcome was. This will guy us a clearer picture.
Thanks
Neill