**EDIT: I also have a bunch of crash logs in the crashes folder if needed.**
I have actually found a serious issue that should be fixed soon, I get this error now and then:
http://imgur.com/a/S0Esp it is very serious because it shuts down the worldserver and I can sometime loose data, any fixes for this?
When you say you lose data, is that only recent data? Like you just put something in the bank, then the server crashed, and the item is no longer in your bank and may or may not be in your inventory anymore? If so, while it is still a serious issue as server crashes are a big deal, you are losing data simply because the server did not save everything upon shutdown.
I'm not sure what could be causing this (maybe someone else knows?). I have never run into this error when I was on v5, and I can't say I've seen anyone report this for v5. However, I know for a fact no one has reported this on v6 or later versions, so when v6 comes out for public release (which is sometime soon), if it still happens, then please report the issue here:
http://www.emucoach.com/forumdisplay.php?51-Bug-Reports-Cataclysm
If it still does happen on v6, then it is likely just your computer, as you could be missing important resources. Still, report it there if it happens on v6 so we can further give you assistance. It's possible the bug was fixed on v6, which is why I say wait until then.