Cannot get RRW to work outside of the Host SBS server. Possible port 4125 issue?

We use SBS R2 SP2 and have issues connecting to Servers or Clients via RWW from outside the SBS server. We can connect from the server itself with no problems. There are no firewalls blocking ports 3389 or 4125 on any server or client on our internal LAN. The edge firewall is confirmed to have these ports open. Netstat -aon confirms port 3389 is listening and returns a PID, but we cannot see any evident that port 4125 is active, even after logon/authentication. Microsoft believes these ports are being blocked and offers no solution to the lack of visibility to port 4125 activity.  We have loaded the latest Broadcom drivers, disabled RSS and offloading, ensured RPC, WMI, Network Connections, Terminal Services, Telephony, Remote Access Connect Mgr/auto connection mgr and RRAS services are running.