When I created my new stack, I told Digital Ocean tu use my SSH key. It said it will not send an email, and that's ok.
But, how I figure out the user name to login using ssh? You don't have any place that tells me so... I don't think that's really common, a lot of other services creates users with varies names, and I think on the Access Tab you should say something like: to SSH, use: ssh email@example.com (of course, changing this IP for the current server IP, this one I typed randomly)
I think it's not clear that the user that have your key is "root", you guys should point that out, I spent almost an hour trying to guess the correct user name (and trying to find on your docs).
So, I really suggest you make this information clear so the next people don't have the same problem that I did...