The top-level online folder is the wwwroot of the yourname.impliedlogic.com website, and this folder usually contains a number of system folders and configuration parameters for the web-server in a root web.config file. To avoid the risk of inadvertent damage by careless use of the FTP service, all such files are masked from the FTP access.
This means that you will not be able to define access rules for the entire website directly. Instead our recommendation is to make the home page open to public access, and then restrict access to one or more model folders as depicted in Typical client folder layout for an eSTEM application server.