I also tried it under different operating systems (Ubuntu, Windows). No chance.
What can be wrong? I mean the upgrade process seems to work - I see the knight rider like LEDs flashing - first from left to right (I suppose, it's the uploading process), then from right to left (I suppose it's the flahing process).
But still, device doesn't boot, or at least is not reachable afterwards, beside going again into bootloader mode.
Is there a way of recovering / flashing via SD card?
Or via RS232 or RS485?