It seems it's been working perfectly again for me the past few hours.

Try port 3122! I'm using 3122.

Oh, man; that sucks.  I hope Coinfoundry support steps in to assist!

Somebody joined; it was at 4 miners and 2.2 KSols/s when I wrote last.  Now it's at 5 / 2.44 KSols/s.  I was hoping you'd managed to get on!  I'm not sure what else to suggest, aside from possibly disabling the firewall and Defender altogether for a short time.  First see if you can get to 127.0.0.1:1880 and then try again after disabling, because that's a way to know immediately - plus the change I mentioned in the number of "Receiving new job" lines.

Let me know how it goes, I look forward to the help with finding blocks!

I had to switch anti-virus programs.  McAfee's whitelisting of the program wasn't working, for some reason; but it still appeared as if bminer was running.  I tested it by disabling McAfee altogether for a few minutes, it took a while, like 20 to 30 minutes to see the results on coinfoundry.  However I could tell immediately if bminer was working properly two other ways: whether the local site opened ( 127.0.0.1:1880 by default), and the console displaying many many more "Receiving new job" lines compared with previously. I then used Microsoft's Defender a/v, and it worked with that but I prefer a more robust security program so I switched to Bitdefender, and it's been running fine ever since.  That was just three or four hours ago.

I'm just another miner using this ZClassic pool; but, I've been using it the past few hours.  It hasn't been down as far as I know.