Membership2 Pro: How to Protect New Post Screen

Hi guys, im having a really hard time protecting the New Post screen from logged-in users that have NO memberships. I want people to submit articles only if they have an active membership. So far I tried the Admin Side add-on and the URL restrictions add-on to no avail. Users have Contributor level by default.

BTW, this is the URL i added into the URL Restrictions add-on:
http://mysite.com/wp-admin/post-new.php

Thoughts? Work-arounds?