Using The Facebook C# Sdk Without A Canvas Application?

Im trying to use the sdk without a canvas application, so have followed steps 1-7 in the quickstart guide up to adding the facebookSettings property in the Web.config.

I have added an image to my page and an onclick event that contains the below code. but when I click the button, it just takes me to the home page (CancelUrlPath).

Changing the Authorizer to a CanvasAuthorizer results in FB loading the login screen, but I get an error 404 not found on the call (even after inserting the handlers into the config)..

fbApp = new FacebookApp();
authorizer = new Authorizer(fbApp) {Perms = requiredAppPermissions};
authorizer.ReturnUrlPath = "http://localhost/User/UserRegister.aspx";
authorizer.CancelUrlPath = "http://localhost/";
if (authorizer.Authorize(this.Context))
{
Response.Write("hello");//never gets here
}