CTDs are difficult to track. You won’t find in the logs anything about it because since the game’s just crashed it cannot output anything to the log, can it?
CTDs in Civ6 are also less common than in Civ5 because imo they changed how the data is stored internally and in save files. It’s more resiliant to missing objects or IDs, because i think they use Type Names internally. Plus the entire DB is full of constraint checks with auto-deletes.
Some warnings or errors in logs may point to a possible CTDs in a moment, but there’s no easy telling which ones if any.
From my experience the main reason for CTDs is when there’s something missing in DB and unfortunately it lacks constraint checks. This may happen with some tables that either a) are missing references and it is a bug b) are multivalue and this is by design. Main offenders are usually Modifiers, Requirements and their Arguments.
It may help a bit to enable Detailed Log for Game Effects subsystem. You need to set a parameter to 4, i think, in AppOptions.ini.
