Frustrated beyond belief...

[orion]

Port changed to 0 (from 8000), ACC shows "Not Ready", accessing files from network is all right: those are weird. I think you should send a support request to asustor. https://support.asustor.com/

[RGauld]

I already have, but as usual, they take days to respond, if they respond at all (less than impressed by their support lately)...
Thing is, what can they do remotely? As near as I can tell, I have been locked out of the AS6204T... So if I'm locked out, how
are they going to gain access?

[sksbir]

did you opened ssh port ? ( I mean before all this happened ) if yes, is it still working ?

[orion]

I already have, but as usual, they take days to respond, if they respond at all (less than impressed by their support lately)...
Thing is, what can they do remotely? As near as I can tell, I have been locked out of the AS6204T... So if I'm locked out, how
are they going to gain access?

If "reset" button on the back of your NAS is working fine, connection problem might be caused by your local PC. I guess they should check your local PC remotely. For example, you said: "IP address blocked out by me for security reasons, but it does show the correct IP, although I noticed the port no longer shows 8000, just "0" ".

And, as sksbir mentioned, you can gather more information through ssh if you enabled it before.