There are two ways you can use to open Preferences Dialog.
Way 1 :
At the top of the main frame of Newzie, you will see a button named 'Preferences'. By pressing, you can open Preferences Dialog and customize Newzie based on your preferences and needs.
Way 2 :
Newzie provides keyboard shortcuts for mostly used actions and one of them is to 'Open Preferences Dialog'. By default CTRL+P key combination opens the dialog but based on your preferences you may customize this key combination. To do so, go to the 'General Keyboard Shortcuts' help topic