This application is a freeware nzb binary newsgroup reader application available on Windows 7 up to Windows 10, 64 bit and MacOS.
On Windows install downloaded msi. On MacOS unzip the app. Then launch nNews application.
If you run into the Windows dialog 'Windows protected your PC' then click on 'More info' and 'Run anyway', more on this here.
Same thing on Macos you will need to enable 3rd part app, see here.
Launch nNews, the configuration screen is popped up at first startup.
Once configuration is done press Test button then Submit. To download nzb just drag and drop nzb file or use menu 'File / Add nzb'.
If you wish to uninstall go to 'add remove programs' Windows control panel and click unistall. Download directory is to be manually removed though. Also config files .nnews and .nnewsstate located in home directory won't be automatically deleted.