In Thor's config.ini file you can set the URL to the page that you want to display in the patcher's box, for example a page called news:
[NoticeBox:Box0]
Width=347
Height=250
Left=21
Top=217
URL='http://www.YOURRO.net/example/news.php'
Are you using the pages/news plugin for your Flux CP? If so, I assume using that URL will probably show the full page, not just the part with the news. In that case one solution could be to:
1. create a new page in a folder of your choice on your server,
2. there, include just the news part of your regular news page with an iframe, or jQuery load the div of your news,
3. and use the URL of your new page in the config.ini instead.
I'm not using the news plugin though, so I don't know if there isn't better way.