This is actually technically a NCP issue as it relates to my purposes, but the same issue applies to WON, so I'm choosing the more active forum.
Essentially, model editing just outright does not work. When you change, say, the leader's NATO symbol or title via the model file, the game will outright just not reflect the changes. What you can do is alter the peripheral files (for example, change the NATO files themselves, so it will read the one you want, or change what the leader titles themselves mean through the strings).
Is there some other location where this data is stored/being extracted from in-game? Why are these changes not being reflected?