Hi Andrea,

I'm very sorry for the delay in answering your message. Generally, you need to retrieve content as a DataSet using Kentico CMS API (TreeProvider.SelectNodes) and then generate an RSS-compliant document and send it to the output. You can find the following articles useful:

http://www.codeproject.com/soap/rssandblogs2.asp
http://www.codeproject.com/soap/weblog.asp

Should you need any help with that, please feel free to contact me.

Best Regards,