The problem with the higher version was exactly the keep alive issue, it didn't work so well. It would have asked me for the password when i wanted to copy files.
Can you please post session log files from both versions, showing the authentication when copying files?
I am using "Sending of null SSH packets." I had 10 seconds, i reduced it to 5 seconds.
Did you try the other mode?
I was hoping that some old WinSCP version would work for me. The problem, is that WinSCP creates a new session every time i open a putty or open file, which requires this OTP.
I hope you understand, that there's nothing we can do about PuTTY authentication. It's a different application.
WinSCP does not create a new session every time you open a file. It creates a session the first time you save any file. And then only, if the session expires (what can be prevented). If yoiu have a different experience, please post session log file.