Here are the steps to configure Little Snitch to allow NetNewsWire proper access:

1. Click on Preferences | Little Snitch
2. Make sure it is unlocked by authenticating at bottom left by clicking on the padlock.
3. Verify that there are no references to NetNewsWire (Edit (skip to 5) or Delete the entry).
4. If there is no NetNewsWire entry click New | Choose Application Find NetNewsWire and select it.
5. (This applies to an edit or a newly created entry) Allow access to ports 443 and 80 for any portal.
6. You'll have to repeat the process for the second port.

Note: You should have two NNW entries when this process is completed.