Whenever i try to add ports in the NAT -- Port Triggering screen, my router just stops working(no connection with network and internet) i have to manually switch it on and off for it to get a connection again. And after all that the ports arent saved. I have no problem at all with adding virtual servers.
More aboutusr9106 router problem port triggering
I suggest you to update the firmware of your router. Go to their webpage, download the proper firmware and upload it into your router.