Hello,
The Multiplayer feature will be available on all platforms including Linux.
The Cyberix3D Multiplayer server will be available only for games that are published on the Cyberix3D web site.
However, You could install your own Multiplayer server on your computer or on some private VPS (VPS is better) for use in Android / EXE apps.
Maybe we will include a test Multiplayer server for Android / EXE just to check that your game is working with Multiplayer, But you will not be able to use it for games in production.
Regards,
Cyberix3D team