I just started playing Witcher 3 at home, and when I found out that GoG Galaxy supports cloud saves I immediately started playing at work as well. When I started the game at work, I was able to sync the cloud save data and pick up where I left off. Unfortunately, the cloud saves don't seem to be updating my progress anymore. I've also tried manually saving my games, but they don't show up on the other device.

Is there a way to force the saves to sync with the cloud?

How much data do you have stored in GoG's cloud? I ask because that's usually a sign that you're over your gig limit.

edit: Oh and if you take what you put for a thread title into google, you'll find quite a bit about this if you want to go ahead and take a look see while you;re waiting for answers:

https://www.google.com/search?q=Witcher+3+cloud+saves+not+updating