For the moment KOReader just writes something like "unrecognized model: <insert codename>" to crash.log and exits.
@0xDEADBEAF: On the H2Ov2 you'll need a recent KOReader release like
https://github.com/koreader/koreader...018.04.12-beta
Also see
https://github.com/koreader/koreader...n-Kobo-devices
Edit: but I just noticed there's talk of an H2O2v2? In that case the obvious thing to try is changing
this line in frontend/device/kobo/device.lua.
Just replace "snow" by whatever the H2O2v2 will have written in crash.log and let me know what happens, as well as the relevant code name.
Edit 2: apologies, I just noticed above that apparently that strategy isn't working out for KSM? In any case it's still worth a try I suppose.
Anyway, KOReader discussion should be taken either to the KOReader forum or an issue on GitHub because otherwise it'd pollute this thread:
https://github.com/koreader/koreader/issues