After fixing this, it turns out that none of the broken .x files were actually being used... Equivalently named .csv models in the same directory were being used, as were identically name .x models in other directories; but just not the ten broken BOMed .x files!
After fixing this, it turns out that none of the broken .x files were actually being used... Equivalently named .csv models in the same directory were being used, as were identically name .x models in other directories; but just not the ten broken BOMed .x files!