Contact author these two days because of my 203SH cannot update without valid SIM inserted. And he asked me to dumped ROM to do that.
The way to dumped ROM is just copy all /system folder, so you can use adb pull system.
And I checked App log, not only rooted phone is required, but some specified APPs, that means each brand need separate apps to be hacked.
btw, the rooting tool seems only for SH-06E and I wont do any further help on it, so do it yourself and have it your own risk. I just tested on my phone.