This feature is available for Premium members. Just make sure that you have the following options selected to "ON" from within your Account Summary page (http://www.filefactory.com/account/)
Direct Downloads - must be set to "ON"
TrafficShare - must be set to "ON"
With these settings enabled, you should be able to transfer a file from FileFactory to another host by pasting in the file URL within the tool provide by the remote host.