manual port forwarding in Panoramic gateway

I just bounced from Cox Tier 2 support -> Cox Internet Tech Dept -> Cox Complete Care -> Cox Customer Escalation Support and none of them really had a clue. I want to enable remote access to my TabloTV (it's an over the air TV tuner with DVR) via the Tablo app when we are away from home. I did this quite easily with the Netgear modem that we recently replaced with this new Panoramic gateway. But the port forwarding area in the Cox WiFi app is not intuitively set up to do this pairing. I have tried every combination I can think of with no success. I simply want to accomplish this...

Public Port ---> Private Port

21685 ---------> 8887

21684 ---------> 80

If anyone from Cox or a fellow customer has had success, please advise how to do this. Thanks.