just a note
its possible to download the machine without a tech call needed
you need to perform this with a USB stick
make a foldder in the root called DWLD , place the firmware in it
power down the machine, press AND hold 4 and energy button, power on machine, with usb stick in, release the 2 buttons when the machine is in download mode
wait a few mins , done
even with a downgrade all settings are still applied :)