Hi there, I can't update the router with third-party firmware. It just stops half-way though and shows the grey square with black background. If I go back the progress bar is going on, but starts from the beginning again after some time. Then it stops with the message upgrade failed in a requester. If I update with the newest firmware (v4.20.7) again it completes with no errors. Sometimes it just shows the grey square with black background saying "updates failing". I'd be glad about any help. Thank you very much, Daffel P.S. How large is the NAT-Table with firmware v4.20.7?