Tested working fine in Chrome, IE9, IE10, and FF. Chrome uses same Engine as Safari (webkit). Enable debug mode and maximum error reporting in Joomla global configuration. Once done press F12 to open your error console and set errors to persist. Now try again and see if any errors show in the log or on screen.
As with all CB Connect and FBC releases if the endpoint can not be reached then it will not work. You need to ensure you've a public and published Joomla menu link, ensure you're not messing up URLs with 3rd party SEF extensions, etc..