Find Sandbox Mod Lobby:
1. Start Wargame Red Dragon and go to multiplayer
2. On the top left of the "computer screen", click filters and make sure all of the choices are checked.
3. Sort by server list by Starting Points, highest to lowest. The name of the server is [SANDBOX MOD]. Password is "modders".
Instructions with pictures are here: Forums.eugensystems.com
Note: This server is only for meeting and chatting, it was never actually start a game.