Hi Neil, thanks for your reply. I kept pressing the low right corner for about ten minutes and nothing happens.
when all the text disappears, the screen becomes red, press the LR corner and then it becomes green, press the LR corner and then blue andthe next click a colour pattern starts moving in the screen. That's all.
No more screens, text or anything, only that pattern moving whatever the number of times I hit the low right corner.
I bought this device two days ago, so, is it possible there's a new "protection"?

I read and checked that unlocked maps don't work on this device. It seems it was from the software version 3.10. So I was trying to get everything sorted out to downgrade it to a lower firmware version or flash the firmware and (as I'm trying to learn how to do it) first step was getting the HWID and back it up. I'm a bit afraid to use a firmware for a different HWID. Does that make any difference?