bannerlord troop trees

Everything from field battles, world map and encyclopedia are fine but the party screen when clicking on one of the edited troop units it crashes?

So I'm doing my own version on the Empire faction, making them more 'Roman' like. I've mostly been busy with changed weapon/armor ID's and adjusting some skills. I can't seem to figure out how to split troop trees. Like, how to make the Imperial recruit be able to be upgraded to 3 different...