thanks a lot for that attempt.
I do not get logged in though:
prompts me for a password for user reader
sftp -P 1124 firstname.lastname@example.org
(which i do not know).
I created a key pair before and copied the public key to the "authorized_keys2" file.
i think a normal ftp instead of sftp could be even more useful. Windows users could connect via ftp in explorer this way (like it was possible by "get_root").
Even better a Samba server on PBs side would be to Windows users.