OK, I've just seen your version info in a comment on another answer.

Given you're using accessing port 80 on server xyz.x.edu I assume a regular webserver (e.g. IIS or Apache) has been set up on that server and the CSP Web Gateway added to it, then configured to connect to an InterSystems instance (perhaps on the same server, or perhaps elsewhere).

In that case, is your webserver set up to dispatch /api/atelier to the 2017.1 instance?

I also have a hunch that if your webserver is prepared to serve HTTP then it may be sufficient to make some server-side settings in Portal on your Caché / Ensemble server, as follows.

The settings are WebServerName, WebServerPort, and WebServerURLPrefix. These can be found in the Startup Settings ([System Administration] > [Configuration] > [Additional Settings] > [Startup Settings])

Doing this may mean you don't need to get each Studio user to change their settings. But it seems possible the server-side settings won't be able to make Studios use HTTPS for templates and add-ins rather than HTTP.