Yesterday I was so close to definitely brick a brand new Cubot GT99… But fortunately I had previously installed a recovery manager (CWM) into my Android… So next steps were only to plug a new formatted SD in the slot and push there a new ROM from the computer… Great!
From this lesson, my advice is:
ALWAYS (always!) HAVE A RECOVERY MOUNTED ON YOUR DEVICE ROOT.
It can save you from getting your smartphone and… throw it down the window!