yaseen (./15) :
for installing the 3.1 Os

Oh, OK, so you need to type that "install product code" command indeed.
As for the PC side, please be patient, Folco will probably come later when he is available. He has much more experience in dealing with pedrom than I have. And of course PpHd may answer too.
That being said I suppose the ./2 procedure I explained back in 2012 should work as it's calling the bootloader directly, and installing pedrom doesn't modify it.