Here is the crash log. This crash occurs whenever changing config settings for the mod:

[22:10:03.376] [Main Thread/FATAL] [tML]: Main engine crash

Tip: This is likely a mod's fault. Disable mods one by one and check if the issue persists

System.NullReferenceException: Object reference not set to an instance of an object.
at BTitles.BiomeTitlesUI.Update(GameTime gameTime) in BTitles\BiomeTitlesUI.cs:line 258
at BTitles.BiomeTitlesMod.Update(orig_Update orig, Main self, GameTime gameTime) in BTitles\BiomeTitlesMod.cs:line 361
at Hook<System.Void BTitles.BiomeTitlesMod::Update(Terraria.On_Main+orig_Update,Terraria.Main,Microsoft.Xna.Framework.GameTime)>(Main , GameTime )
at SyncProxy<System.Void Terraria.Main:Update(Microsoft.Xna.Framework.GameTime)>(Main , GameTime )
at Microsoft.Xna.Framework.Game.Tick() in D:\a\tModLoader\tModLoader\FNA\src\Game.cs:line 488
at Microsoft.Xna.Framework.Game.RunLoop() in D:\a\tModLoader\tModLoader\FNA\src\Game.cs:line 878
at Microsoft.Xna.Framework.Game.Run() in D:\a\tModLoader\tModLoader\FNA\src\Game.cs:line 419
at Terraria.Program.RunGame() in tModLoader\Terraria\Program.cs:line 266
[22:10:03.377] [Main Thread/DEBUG] [TerrariaSteamClient]: Send: shutdown