Thanks for posting to the forums!
Since you are still unable to connect to you Slingbox PRO-HD from a remote Wi-Fi network, I recommend checking your port-forwarding settings within your router to make sure you entered the correct (LAN) IP Address for your Slingbox and the correct port that your Slingbox is using. To verify the (LAN) IP Address that your Slingbox is using, please follow the steps listed in this article:
As for the port, the PRO-HD will only use one of the following ports on your router:
These articles will provide additional information about the port forwarding process:
This website will also provide you with step-by-step instructions for port forwarding your specific router:
Hope this helps!
Sling Media Moderation Team