Torrenting Broke After Firmware Update to 1.0.0.76 - Model: R6120

Hello - About two weeks ago I logged into my router (don't remember why at this point) and saw an available firmware update.  I shutdown anything I had using the network (including Transmission QT and Cyberghost VPN) and installed it.

I reconnected to Cyberghost fine, but Transmission now reports that port 51413 is closed.  Here's the bizarre thing (to me at least).  When I disconnect from Cyberghost, the port shows as open.  I would "blame" them except that I was successfully torrenting through their VPN servers up until about 45 seconds before I started this firmware update.

I have contacted Cyberghost and exchanged several emails with them, but I feel like their tech people are in over their heads.  The last email from them told me they were closing my ticket because they don't support port forwarding (only port forwarding involved is on the router so I can listen on 51413).  It's been frustrating.

I'm considering rolling my firmware back to 1.0.0.72 just to see if it fixes this, but that isn't any kind of long-term solution.  *Any* advice would be tremendously appreciated.  I'm using Windows 10 Pro, Kaspersky AV, and the built-in Windows firewall.

Thank you    :)
Will in Missouri - USA