What does this mean?: [Form_Button_WFlow] Column 'BUTTON_ID' cannot be null

What does this mean?: [Form_Button_WFlow] Column 'BUTTON_ID' cannot be null

Since there's no duplicate stateless form option, I'm attempting to paste a form definition with action into a blank stateless form definition. It's giving this error.

Since it will not let me save the form, I cannot share it to support in any way...

Cheers,
John Whitney