By far the biggest issue we have seen at HSTi is the issue with firewalls on the PC preventing file sharing from actually happening. Most people don't think to check their firewall settings because certain firewall software (Such as Norton 360, etc) come installed on their PC when they buy it.
If you have setup sharing, and are still having issues (ie, the setup wizard says sharing is NOT setup) then PLEASE look at turning off your firewall, or at least opening up the firewall to allow sharing to occur. Each firewall is different but you need to either enable 'file sharing' by setting up your home network to be 'trusted' or else open the ports for the firewall to work.
The ports required are -
TCP/UDP - 135-139
TCP/UPD - 445
Or better yet, just turn the firewall off all together. If you have a wireless router (or any router) connected to the internet, then you already have a firewall on your network.
If you need more help, feel free to