Multi user mode in Sage is simple on paper. More than one person working at the same time on the same file With no interruptions. In real life, this's the place where the majority of Sage users have trouble staying on task. For a while, everything is in order. Then Sage shuts down, freezes, disconnects users, or shuts down completely. Sometimes it throws an error. Sometimes it just vanishes. There is no warning. No explanation. ...