CTD after becoming an emperor

Mosash

Game version : 1.5.1
Build : 13871.1953281

Detailed description:
After becoming an emperor (me gongsun zan, the 2nd turn player) the other player (Sun jian) gets the turn and then the crashes happen at 4 different incidents :-
1- When anyone player vassalage any other faction.
2- whenever a player closes one of the notifications after becoming an emperor (we don't know which notification though)
3- When sun jian enters a battle and delegates(he has an army lead by huang gai taking a copper mine from yan baihu).
4- We did a save file just before sun jian taking the copper mine and after closing some (not all) notification bubbles, the game crashes whenever loading at this point.

Reproduction Steps:
For the vassalage, we've managed to work around it by reloading and closing notifications so I don't know how to produce it.

For the notification closing :-
1- Load the Auto-save file
2- End gongsun zan's turn
3- wait for the cut scene or skip it
4- during sun jians turn, either player closes all notifications by right clicking their bubbles, eventually one player will cause a crash.

For the crash after the battle :-
1- Load the Auto-save file
2- End gongsun zan's turn
3- wait for the cut scene or skip it
4- during sun jians turn, use the army lead by huang gai to attack the copper mine close to it, delegate the battle
5- the game crashes after the battle ends and the results are shown.

For the other save file:-
1- just load the quick-save file
2- the game crashes during loading.


Attempted solutions :-
1- Verifying the integrity of game files

Mosash

So this section is dead or?

steam_164509111509lgFwRVj

Same here