The Enhanced Edition for GOG should include Galaxy support; that was mentioned in one of the Kickstarter updates after Galaxy was first announced, so unless something changed since then, it should be in. GOG even initially wanted to delay selling D:OS until the launch of Galaxy (when the ETA was expected to be a couple months).
That's funny, I was not even aware of that fact. And with the galaxy client being only in beta at the release Witcher 3, it appears we will still have to wait a little while.
