They're going to say "closed" until you have an application running on your system that's listening on those ports. Are you running that application when you test to see if the port is open?
I'm not sure that's quite true. I think that Bitorrent tester is looking for a response (even if it's a refusal), rather than a connection.
I just tried "port forwarding" TCP Port 555 inbound on my SBS 2003 server with ISA Server 2004 installed. In ISA, I "published" a server on TCP Port 555, which is the equivalent of port forwarding on a hardware router.
Before creating a new ISA firewall rule dealing with TCP Port 555, the BiTorrent checker reported "An error has occured! Port 555 does not appear to be open."
Then, I "published" a server at TCP Port 555. I HAVE NO APPLICATIONS on my server listening on TCP Port 555. I have no ISA "listeners" set up on TCP Port 555, either.
If I use the following command in DOS:
--- netstat -an |find /i "listening"
it shows nothing listening on TCP Port 555.
But that torrent checker says, "OK! Port 555 is open and accepting connections". You will be able to receive incoming BiTorrent connections.
I looked at my ISA Server logs and see that if I disable the firewall server publishing rule, ISA Server flatly rejects the inbound request on TCP Port 555, since it's unsolicited and isn't allowed by any firewall rules. But if I enable the firewall server publishing rule, ISA Server allows the request, but the connection fails: "No connection could be made becaue the target machine actively refused it."
In the first case, ISA is just dropping the request. A The Bitorrent checker says there's an error. In the second case, ISA allows the request, but the server itself actively refuses it. But it passes the Bitorrent checker.
Similarily, when I enable the publishing (forwarding) rule, GRC's "Shields Up" probe shows TCP 555 as being "Open", but "unknown application for this port". If I disable the publishing rule, "Shields Up" reports a Stealth connection because the incoming requests have been dropped by ISA.
I'd double-check for hardware or software firewalls on that PC. If you are running BiTorrent software on the PC, come in from another PC on the same local network and telnet to the PC on TCP Port 47624:
--- telnet 192.168.2.235 47624
and see if you get a response.