... less than 2 seconds ...
The update should last longer: about 1 or 1.5 minutes if I remember well.
After the "update": is the Mambo.plf file still in Mambo's root directory or is it empty?
The update should be successful, if the file is gone.
If you choose the drone box on the startup screen of FF Mini: which "Software-Version" and "Hardware-Version" are shown there?