I just came to see if there was a solution to this problem. Every time I reload the game, the races I disallowed for my faction, default back to "allowed". Naturally I get a caravan 10 seconds after starting the game, and a freak-fest of medieval-fantasy races stroll in my viking themed faction capital... kind of a buzzkill. I will add that I am using Rim war with this mod, and as such my own faction is sort of my vassal, not sure if that's relevant. Would love to see a fix for this.