AFK issues

I started playing this server 2 days ago and in the following 2 nights i've left the game running over night.
During both those nights it seems like the game crashed 1-2 hours into the night.
Does anyone know what is causing this? I have no problems with the game the entire day im at the computer but at night it goes nite nite.
Is it possible screen shutting off has something to do with this?

Help much appreciated.

 

UPDATE:
We were facing some instability issues and disconnections, thus a maintenance was performed yesterday in order to fix them. Let us know if you still fail to remain connected.