I don't mean a dialogue file, I mean your character died and "dialogue" slot in his character file also died... in a way.
I was right - the value went back to MULTIJ.DLG instead of O#KORIN.DLG. Okay, fixed - should be working now. Check your mail.
Now, in case I'm not around, here's what you(a general you - just a player whose game crashes when one particular character is supposed to talk) can do. It's a very-very rare case, it'll likely never happen to you, but the engine is not meant to handle talking NPCs in party, so everything can happen.
1) Install Java. Yes, Java.
2) Install Near Infinity. You can find the link in the modlist
http://modlist.pocketplane.net - or ask around.
3) Open "open game" in Near Infinity. Choose Chitin.key in IWD directory.
4) Open "open file" - external file - choose .gam file in your saved game directory. There's only one file, ICEWIND.GAM.
5) Go carefully and find Party Member 1. (Same goes for Party member 2... Party member 5. Party member 0 is your PC. Always.)
6) Press view/edit button.
7) In the new window, select the bottom slot. It's called CRE: Signature. Press view/edit button.
Let's suppose it's Teri. Her OVERRIDE SCRIPT slot should be O#TERI.BCS, her SCRIPT NAME should be O#Teri, and her DIALOG should be O#TERI.DLG. In other words, it's O#TERI, O#TERI, O#TERI. If it's not, you must edit these fields. How? Press the right mouse key and choose Edit as String. Then save.
That's it.