Cyber Gadget Retro Freak console, any thoughts or experience?

[Profeta Yoshitake]

Hi there, RetroFreak owners.
My RF arrived yesterday and I'm already freaking out.
It came with firmware 1.1 and when I tried to update to 1.5, the console stalls just after the reboot countdown ends.
I tried again a couple of times and it was the same.

Any workaround? I want my RF updated to 2.5...