I understand that you are having some issues in order to get the remote connection to your Slingbox PRO-HD.
Although there was an outage some weeks ago, this has nothing to do with your Slingbox issue. The outage prevented some customers to log in to their accounts, but in your case you say that the Slingbox can not stream the signal.
In all case, I recommend you to reset the Slingbox and run the Setup Assistant for Internet Viewing one more time. If you do not know how to, just check the following links.