Hi all, I too have just bought a dso 201 and have had issues updating firmware… my dso doesn’t support the win based firmware upgrade tool but has the ‘power on holding down key’ which results in an extra usb drive opening up… after many tries of different firmwares resulting in powering up to a blank screen have found a fix which may work for some. Download the hex files Alf has posted, power up with down key to bring up ‘ext drive’… copy/paste/drag APP/LIB one at a time, wait for ext drive to dissapear then appear with ‘filexx. RDY’… then leave for 10 seconds or so… then power off dso and power up again… all should be good 
for some reason if you cycle power too quick after files show up it wont work… hope this helps a little:)