It seems to be a little different from my system, since only the primary computer shows in the Network map, Unless I turn off IPv6. Then all the computers show up. Of course, IPv6 is necessary for running a homegroup. I may need to do some research and figure how to set the IPv6 addresses so they will work together.
But I have always had the ability to connect to my other systems either through the homegroup or normal networking. I just don't use homegroup because it only allows (unless you add folders to the libraries) access to certain areas. But if you have a shared folder on another computer in your network, and it is set to share with a homegroup, or specific people, you should be able to access it.