I've actually caught a few things with CLua when it crashes.
1.Start it running with F10,
2.Wait and watch things die.
3.The games GUI will start to flicker slightly.
4.After a few minutes of this happening the GUI will completely disappear.
5.Next textures will start to vanish until you're left with a black screen, the game is still running and you can hear the script is still running.
6.Eventually the client will crash after the previous happens, sometimes with an error report, other times not.
This will usually start to happen for me after roughly 1 hour or so, but its sometimes sooner and sometimes later. I'm no expert or anything but it looks like the game is using some sort of timing that might be getting broken by the LUA calls or something. If I can offer anymore details I'd be glad to help out in any way