If you enable the Proficiency Die option in the OGL sheet, the script ignores the 'die' portion of constitution_save_bonus, leaving you without any proficiency bonus for the Concentration check. It also doesn't incorporate any Global Save Bonuses (global_save_mod), like what a Bladesinger may have setup for intelligence_mod while Bladesong is active.
If you enable the Proficiency Die option in the OGL sheet, the script ignores the 'die' portion of constitution_save_bonus, leaving you without any proficiency bonus for the Concentration check. It also doesn't incorporate any Global Save Bonuses (global_save_mod), like what a Bladesinger may have setup for intelligence_mod while Bladesong is active.