Luis Guzmán’s personal site hosting several useful tools and documentation for not only Open General, but SSI Panzer General II and SSI People’s General too.
You can find all map images and their map descriptions used in OpenGen / PG2 campaigns in various formats on the Mapfinder.
Most of the active community players and designers are members of the OpenGen Forums, if you have questions about Open General, this is the place to find support and up to date information on Open General development.
Also you can check OG Challenge Campaign Forum to enjoy the experience of playing specific campaigns at the same time as other players. This is a fantastic way to learn the game and connect with other players.
We use our Facebook page to announce the latest improvements, new installers, campaigns, and to promote events like Campaign Challenges, or simply we maintain contact with those players who are more comfortable with social media than old school forums.
The Polish Open General Community provides dozens of campaigns for EFILE_GUS, which is not part of the official installers.
Panzerliga is the most active forum for online / PBEM players.
German Open General Forum on Rayydar’s PG3D (the German name of the PG2) forum for German-speaking players and designers.