Unlock jungle mills early for Brazil

[Codenaugh]

I copied the Lumbermill to make a unique improvement Brazilian lumbermill that unlocks for jungles at the same time as regular lumbermills (Construction tech). I can get it to work, and the tile shows the new yields, but it appears like there is no actual improvement. How can I re-use the art from lumber mills for my new unique unit? I'll post my sql code below:

INSERT INTO Types (Type, Kind) VALUES    ('TRAIT_CIV_IMPROVEMENT_BRAZIL_LUMBER_MILL', 'KIND_TRAIT');

INSERT INTO Traits (TraitType) VALUES ('TRAIT_CIV_IMPROVEMENT_BRAZIL_LUMBER_MILL');

INSERT INTO CivilizationTraits VALUES ('CIVILIZATION_BRAZIL', 'TRAIT_CIV_IMPROVEMENT_BRAZIL_LUMBER_MILL');

INSERT INTO Types (Type, Kind) VALUES ('IMPROVEMENT_BRAZIL_LUMBER_MILL', 'KIND_IMPROVEMENT');

CREATE TEMPORARY TABLE tmp AS SELECT * FROM Improvements WHERE ImprovementType='IMPROVEMENT_LUMBER_MILL';

UPDATE tmp SET ImprovementType='IMPROVEMENT_BRAZIL_LUMBER_MILL', TraitType='TRAIT_CIV_IMPROVEMENT_BRAZIL_LUMBER_MILL';

INSERT INTO Improvements SELECT * from tmp;

DROP TABLE tmp;

INSERT INTO Improvement_ValidFeatures (ImprovementType, FeatureType) VALUES
    ('IMPROVEMENT_BRAZIL_LUMBER_MILL', 'FEATURE_JUNGLE');

INSERT INTO Improvement_ValidBuildUnits (ImprovementType, UnitType) VALUES
    ('IMPROVEMENT_BRAZIL_LUMBER_MILL', 'UNIT_BUILDER');

INSERT INTO Improvement_YieldChanges (ImprovementType, YieldType, YieldChange) VALUES
    ('IMPROVEMENT_BRAZIL_LUMBER_MILL', 'YIELD_PRODUCTION', '1');

INSERT INTO Improvement_BonusYieldChanges (ImprovementType, YieldType, BonusYieldChange, PrereqTech) VALUES
    ('IMPROVEMENT_BRAZIL_LUMBER_MILL', 'YIELD_PRODUCTION', '1', 'TECH_STEEL');

INSERT INTO ImprovementModifiers (ImprovementType, ModifierId) VALUES
    ('IMPROVEMENT_BRAZIL_LUMBER_MILL', 'LUMBER_MILL_RIVERADJACENCY_PRODUCTION ');