If you have your network set up properly, the SME will show up in Network Neighborhood. You may need to look under "Entire Network" to find it. Make sure you're using the same workgroup/domain settings.
Yes, that's the command to install an RPM. If you install the "Update System" addon, you'll be able to install RPMs from your local machine via the Server Manager.
The port forwarding RPM will add a panel to Server Manager. Most SME addons that require configuration do as well.