WSN Links can perform necessary FTP operations such as chmoding for you if you supply your FTP info on setup or at Admin -> Settings -> System Configuration. If your FTP changes on a site move, be sure to update the info on the system configuration page.

FTP Host: typically ftp.yourdomain.com
FTP User: yourname
FTP Password: the password for the user
FTP Directory: the path you follow to reach your WSN Links install from where FTP drops you. Do not include a trailing slash. Typical example: public_html/directory

Some servers don't have PHP's FTP extension loaded, and so cannot use this feature.