Server edition on Linux is no longer to be launched with mono command but you can simply launch it directly ./ManagerServer.
I’m also experimenting with distributing server edition in AppImage format. This means, it takes only 3 very simple lines to “install” and launch ManagerServer on Linux.
wget https://github.com/Manager-io/Manager.AppImage/releases/latest/download/ManagerServer-x64.AppImage
chmod a+x ManagerServer-x64.AppImage
./ManagerServer-x64.AppImage