What NWBC version? What AS ABAP version?
No additional configuration is required to enable the side panel. The side panel will become visible on the right side of the screen (you still need to expand it by pressing on the arrow icon) as long as the application alias assignment succeeds. For example in your case if you want to display www.sap.com in the side panel in transaction IW33, all it takes is to define the application alias {TR=IW33} for the web page defined as side panel (Node Option = Side Panel). See the application help and the attached screenshots for details. Notice that you may have to restart NWBC in order to see the changes.
