Some new information: It appears that the client-screen freeze was due to a glitch in my broadband connection; a new, stronger WiMax signal came online and my modem did a reacquire, interrupting the connection for a minute or so. Interestingly, I found that the modem password had reverted to the factory default. I thought the same glitch might have affected the port forwarding, but found nothing different. In any event, t seems to me that loss of port forwarding on the client side could not have been the cause since I am connecting via a VPN which uses port 4433 (IIRC), and the VPN was still operative – I was able to ping the server machine and SSH into it after the event occurred.
I had in mind to try reinstalling 4.3.30 at the client end, but found this morning that the computer had inexplicably died during the night, so the whole matter is temporarily academic until I can replace that box. Meanwhile thanks for your attention, and I would like to take the opportunity to put in another plug for a way to disable auto-scrolling in the client window – it’s the ONE feature of NoMachine that I find highly annoying.
– dhfx