OK.... well i got it to work ... sort of....     So it appears now when the attribute box is checked.... unfortunately it refuses to animate or show my texture.    The path to the texture is correct.....   am i missing a specific section required within the model sections?   class Attributes { class PRACS_flag_attribute { control = "CheckboxNumber"; defaultValue = "0"; displayName="Glorious Display of Patriotism"; tooltip ="Glorious Display of Patriotism"; property = "PRACS_flag_attribute"; expression = "if(_value isEqualTo 1)then{_this forceFlagTexture '\PRACS_SLA_EXT\flag\flag_north_co.paa'}"; }; };   EDIT: FOUND THE PROBLEM   Mod conflict between current Dev branch proxies and current versions of either CUP Terrains or CUP core.    above code works just fine with them disabled.