Yes, I checked several times to be sure.
Trying to recheck what I did wrong -- the 3.11 zip file I transferred to the 3.11.0_source folder was this one:
Mark 5 Hardware : New Aura (and probably the Aura H2O)
(4d8eac1207, 16 Oct 2014)
72.9 MB - 74,690 KB - 76,481,595 bytes
from this thread here:
https://www.mobileread.com/forums/sho...d.php?t=185660
I don't know if that is indeed the correct 3.11 file for the H2O?