Overriding the default Register page in a plugin.

Hi.
I need to override the default behavior of the Register page and add a few fields to it. I have created a plugin which should do the overriding. In that plugin I have the RouteProvider.cs which is like this:

namespace Nop.Plugin.Misc.MyCustomPlugin
{
    public class RouteProvider : IRouteProvider
    {
        private const string NAMESPACES = "Nop.Plugin.Misc.MyCustomPlugin.Controllers";
        private const string CONTROLLER = "MyCustomPlugin";

        public int Priority => int.MaxValue;

        public void RegisterRoutes(RouteCollection routes)
        {
            routes.MapLocalizedRoute("Register",
                            "register/",
                            new { controller = CONTROLLER, action = "Register" },
                            new[] { NAMESPACES });

            
        }
    }
}

But this causes an error that the route names must be unique. If I change the name of the route then it installs fine but does not override the register page.

I have successfully overridden the About page with this route:

routes.MapGenericPathRoute("Plugin.Misc.MyCustomPlugin.GenericUrl",
                "{generic_se_name}",
                new { controller = "Common", action = "GenericUrl" },
                new[] { NAMESPACES });

Which confuses me a bit.

How would I go about redirecting the register link to my own controller and method (action)?