AppModelv2-WebApp-OpenIDConnect-nodejs | js web app using OpenID Connect authentication with Azure | Azure library

I'm trying to set up Azure AD v2 from http://aka.ms/aaddevv2 using https://github.com/AzureADQuickStarts/AppModelv2-WebApp-OpenIDConnect-nodejs (master branch @ b752987b7367fc92692ac538e1fc24cb400d0fbc), however I can't seem to log in with accounts created outside of the user who created the the app at https://apps.dev.microsoft.com/?deeplink=/appList.

On the apps.dev.microsoft.com end, I have:

• the Application ID, and have created a password which I've used in the clientID and clientSecret respecitively in the config.js file.
• Added http://localhost:3000/auth/openid/return under Redirect URLs
• Have User.Read for the Delegated Permissions section

Is there anything else I need to set up? Am I missing something in the code?

The error I get when logging in with accounts outside of the setup account is:

Sign in Sorry, but we’re having trouble signing you in.

AADSTS50020: User account '[email]' from identity provider 'live.com' does not exist in tenant 'Default Directory' and cannot access the application '[clientID]' in that tenant. The account needs to be added as an external user in the tenant first. Sign out and sign in again with a different Azure Active Directory user account.