Hi there, alas 4.4 didn't work either: downloaded OK, burned to little flash drive OK (browsing shows correct looking files), boot the T510 with flash drive seems to work as it sits there for 5 mins with white underline-cursor blinking at top-left of black screen, then boots - and is still the same firmware 3.8.13!!!!
I think I'm forced to have to advise the client that these are not upgradeable devices
