CTD after taking Birka as elves in 2nd turn

Playing as the high elves, it's at the end of the Rebel turn (rebel army attacked my siege), I win, I take the settlement and it crashes with Sigma...
I play a dwarf campaign and an empire campaign without any problem, not a single crash ever.
What could be the problem?

Hmm seems like my high elven campaign crashes after 2nd turn whatever I do... relaunching a new campaign, same result, several times. Always when the Rebel turn is over and it's my turn again..
I dont have any crash with any other faction...

Can you check the log file in Medieval II Total War/logs?

I have only a warhammer_system.log in it and it's huge, not sure you want me to copy the whole thing... even the last second of log before the crash is like 400 lines

Sure, what should I be looking for in it?

M2TW.system.log.txt should be in there. Open that and copy and paste it here.

Upload it as an attachment, if you can.

warhammer_system.log.rar

done, had to zip it cause the server was timing out...
btw thanks for looking at this

Question: Which version did you download? Was it regular 1.5.1, or Gigantus' version, and did you use the appropriate patches? As far as I'm aware the "Sigma preserve us!" quote is unique to Gigantus' RoDG, but your file structure is Call_of_Warhammer, like the regular 1.5.1 version. And holy crap is that a big file, alright. O_O It seems to have a message for everything loading. Hmmm... I dunno if I can help you. I run Gigantus' version, and the error logs are MUCH smaller, to the tune of ~960 bytes instead of almost 14 megabytes. This is unfortunately over my head, hopefully someone else can help you.

Seems like I have figured it: if I hire an elven priest, then it crashes. If I remove him from my hiring queue, then no crash and game runs normal. Hope they are not needed to win

Nope, luckily CoW is a very expansionist friendly mod, without severe culture and religious conversion penalties. All I could see about priests in your big error log was missing .tga files. Oh well, as long as it's playable again.