The fix in #308 also worked for my Z50-70. Installing the mainline 4.14.9 kernel unlocked the BIOS and allowed for changes to be saved and I can boot from USB again.
Also, I then reverted to the "fixed" Ubuntu kernel (4.13.0-21-generic #24-Ubuntu SMP) and the BIOS is still unlocked and functioning properly.
The fix in #308 also worked for my Z50-70. Installing the mainline 4.14.9 kernel unlocked the BIOS and allowed for changes to be saved and I can boot from USB again.
Also, I then reverted to the "fixed" Ubuntu kernel (4.13.0-21-generic #24-Ubuntu SMP) and the BIOS is still unlocked and functioning properly.
Thanks medpc and ark987!!