Just noticed something else which is odd in your log:
125 Data connection already open; Transfer starting.
That seems strange to me since the directory listing should be the first thing which opens the data connection. Could you try completely exiting Opus and then restarting it and connecting again? Do you still get that message in the log?
It may be worth a try to toggle the PASV option on the FTP site's bookmark entry in case that helps as that has an effect on how the data connection is made, but if it doesn't help then please set it back to what it was.