If you want to downgrade the NAOqi version of your Pepper, you first need to know that it is not possible to do it on your own because it requires specific softwares and tools to downgrade both the Head and the Tablet of Pepper.
The robot must be sent to one of our Service Center so please contact us if you are really willing to proceed to a software downgrade of your robot .
Important notice:
It is absolutely not recommended that you try a NAOqi downgrade on your own with the opn files because this will result with an downgraded Head and not the tablet and your robot won't work properly anymore!