That being said, there are no libraries to provide low level TCP interface provided by Genero
well there is
http://4js.com/online_documentation/fjs-fgl-manual-html/#fgl-topics/c_gws_COMLibrary_004.html to be on the client-side of TCP communication, and this example
http://4js.com/online_documentation/fjs-fgl-manual-html/#fgl-topics/c_fgl_ClassChannel_tcp_sockets.html showing use of base.Channel to implement basic TCP client and server.
However both of the above are unlikely to be used in a web services scenario.
Can someone point me in the right direction ...
With Web Services, you will either be a "server" that exposes a service, or a "client" that consumes a service. You say "I am trying to receive an XML document over http" but you don't say if that is because you asked for it i.e you are a "client", or if you are sitting waiting for someone to send it in which case you are a "server".
http://4js.com/online_documentation/fjs-fgl-manual-html/#fgl-topics/c_gws_concepts_001.html Wether you are a "client" or a "server" is something that you'd need to establish at the beginning and will dictate the code path you take.
The "server" typically sets the rules and will typically have some form of documentation detailing access to their service. Your support contact should be able to interpret that document and point you in the right direction.
Reuben