@chnorton could we add a link to https://support.zendesk.com/entries/26579987 when a API test doesn't isn't successful? This is a placeholder article at the moment, however we'll make it public in the next couple of weeks. This will hopefully help people self diagnose a little more before needed to contact us.

Text should be: "
Connection to Zendesk API failed.
$e->getCode() . ': ' . $e->getMessage()
Troubleshooting tips can be found at https://support.zendesk.com/entries/26579987
"