Making member-only pages using resource groups

Using this great tutorial here:
http://rtfm.modx.com/revolution/2.x/administering-your-site/security/security-tutorials/making-member-only-pages

I have set up a nice little members only section on my site. However, there's a slight problem. When an anonymous user (i.e., not logged into web context) tries to access any resource in the members only group, they get redirected to the 404 not found page. Why aren't they directed to the unauthorized_page defined in modx system settings?

Have thoroughly searched the forums and nobody has an answer to this.
Flushed permissions, checked the roles and policies. Everything is exactly as outlined in the tutorial.

http://bobsguides.com/revolution-permissions.html

See the section toward the end on "Unauthorized versus Error Page"

Give anonymous usergroup "resource group" access, but only "Load only" policy. That's what you need to do.

@Paulp and @bertoost, thank you! that worked great. you both rock.