the new update (i think 1.20) is not on gog yet, at least not for me
It has been on my GOG library already. But GOG server is fuller than Galaxy: 5 hours for downloading 2.5GB from GOG and almost 3hs for 5GB from Galaxy....
As new Marcin's quote prays: "Be a little patient"
Edit: BTW, I've not played SoH yet, so do you, people, advise to play it before or after I'd finished the main plot?