Nicholas,
Please post the RSS URL that you are having issues with, Also provide Yahoo Pipes RSS URL.
Couple of things to check -
1) Can your DMP reach out to the Internet ? Try www.cisco.com or www.google.com in the "URL to be displayed" on the DMP-GUI.
2) What is the code version you are running on the DMP ?
3) What is the hardware model of your DMP ?
4) Is your DMP using any Proxy?
5) Is your PC and DMP on the same subnet ?
Regards,
Sagar Dhanrale