Have you tried it in Passive mode (FTP > Firewall > top option)? I think that's what FileZilla uses by default, but you're using Active...if that doesn't help, can you post a copy of the part of the FZ Message Log that succeeds where SE fails?
This assumes you have actually tried to LIST the contents (manually)? Note that the Test feature in SE doesn't try to LIST - that only happens on a full run. It's the server raising/declaring the 550 error after we send a perfectly valid command - we're only reporting what it said.
This assumes you have actually tried to LIST the contents (manually)? Note that the Test feature in SE doesn't try to LIST - that only happens on a full run. It's the server raising/declaring the 550 error after we send a perfectly valid command - we're only reporting what it said.