It's been quite some time since I started this thread, and although I manage to solder the new EU z-wave chip never said how it went, I tried with my older Q50 to see if it proved successful to then do it in my S70 if it did.

As Sydinstaller thought, it did not work on the Q50 so I did not go any further with the S70, I really thought it was going to work the first time I powered the Q50 as it said it needed to update the firmware:


I then pluged the remote to the computer and it was asking to update the non-existant firmware for the Z-wave:










But then looking in the remote it did install the US firmware again altough the chip is the EU one, so there must be some other chips that need to be reflashed for this mod to work. A real pity as it was a cheap mod: