First of all, did you try installing the RPM you downloaded from openrepos, either one of the 2 apps ?
In theory, there is little changes for the keyboard layouts since first SFOS release, so they should just work.
If not, I checked the RPM and the extracted files, and most of those additional files are related to the spacebar and arrow keys. If all you want is Herbrew layout, then I suggest you just modify he.qml and replace SpacebarRowArrowHe
with SpacebarRow
(line 52), and replace the import "../custom-he"
with import ..
.
Then copy both files he.qml and custom_he.conf to this folder on your SFOS phone: /usr/share/maliit/plugins/com/jolla/layouts/
, and restart (or type killall maliit-server
in SFOS terminal).