Spring RTS Engine

When I'm hosting and get "No response from ..." and "Delayed response from ..." my game crashes.
Also before crashing, sometimes lua widgets start to mulfunction.
eg.

error = 1, Call_DrawScreenItems, LuaUI\Widgets\UnitGroups3.lua:983: attempt to perform arithmetic on local `left' (a function value)
Delayed respone from [WarC]NOiZE (353 instead of 534)
error = 1, Call_IsAbove, LuaUI\Widgets\UnitGroups3.lua:428: attempt to index field `?' (a nil value)

It also happened on my own widgets too.
I've checked lua file but code seems to be ok.

Can you split this into two threads? One for each problem? And post the relevant lua code?

Also that isnt a crash bug, thats when you loose connection to everyone, I take it your not running a supercomputer? Or have a terrible connection? If spring crashes you'll get a BSOD, a 'spring.exe has stopped responding' or a dialog saying "spring has crashed please send infolog.txt to .."

Operating system?
Cpu?
GFX Card?
Service packs?
internet connection type?
Connection speed?
Wifi? Router based network or p2p type(no router, gateway PC + ethernet cable to other PCs)?
SVN build or 0.74b3?
logs?

There's a mutex (used for coordinating multithreaded access to limited resources) lock issue with Lua if you are hosting, either turn Lua off when hosting or use a Springie as the host.

trepan released a fix for that bug in the development forum some time ago.

Yes but it's not in the default install.