That's exactly why we're asking which ports are required.

So far we've opened Ports 80, 4110, 5053, 5056, 50001, but no luck.

RTI tech support gave us ports 5053 and 5056, which does not appear to be correct.

Now we're sunning a port scan between port 1 and 65535. Maybe we'll have an answer on the open ports after a few days, but we don't really have the time to wait that long.