Hi everyone,
Please excuse the intrusion, just wanted to suggest two things:
Have you disabled the form.AutoManaged? This will prevent B1 from managing the modes (note that you'll have to do it).
Can you change the id of the button (id 1 is a special Id telling B1 it's the "Add" button, same for Id 2 "Cancel")?
I'm only suggesting this because it seems you want to control the mode changing of the form yourself.
Hope it helps.
Good luck.
Best regards,
Pedro Magueija