@Michael.Schwartz,
Yes, I have manually created 2 users in the Gluu server to test the authentication, and validated them with the login page.
I created a test client on OpenId Connect. Not sure if I have the correct 'Redirect Login URI'; I'm working on validating it.
On the ASP.Net side, I'm using 'Microsoft.AspNetCore.Authentication.OpenIdConnect' nugget package.
I'm also reading your book 'Securing the Perimeter', but it's too high level and there's no way to access to samples you mention in Github.
That's why I asked for guidance.
Best regards,
--JP