Interesting thing I have discovered whilst attempting to setup ngrok (https://ngrok.com/) with the rest api to come back to local host, when you get the metadata page to come up which it will do quite happily any link you click on is unfortunately not going to work because the URLs have been derived to include the port number so http://ZZZZ-----.ngrok.io gets translated to http://ZZZZ-----.ngrok.io:81 if 81 is the port you are bound too.
Is this likely to be an issue with routes themselves on the api or is this just a symptom of the ServiceStack plugins that generate the web interface?