For the FTP:
Do you have the remote IP from the ftp server whitelisted? This is a common problem why you cannot connect. Is the remote server FTP, FTPS or SFTP?
Empty database:
What options have you ticked on for the backup? Also I would think it might be normal. As it would get populated via the config of the users when restoring right? Because if you would restore it on a new system with another DA for example it also populates the already existing da_roundcube database