Remote Control fail.

Hi, I'm new to this software and I seem to be having problems trying to deploy it onto my test network. I can not get remote control to go onto anything other than the local host machine (win2k3). I've tried the suggested KB links, running the agent install with the VBscript files via CSCRIPT to no avail. All NAT policies, to my knoweledge, are correct. I've tried with the firewall disabled on the remote machine and still nothing. I've tried to remote into the following:

Windows 7, same domain AD as local host and same LAN. (I know, it's beta OS, but it's not in the real network so it's not going to kill me for it to not work here)

Windows 7, same network, but in WORKGROUP.

Windows XP, WORKGROUP, across WAN.

Windows Vista, WORKGROUP, across WAN.

The Vista and XP machine show as "The RPC Server is unavalible", whereas the Win7 do nothing at all, so I'm not holding my breath on Win7 functionality presently :)

This product looks really neat and I would love to get it deployed in the sandbox, any help would be much appreciated! Thanks!