I have The Witcher 3, and while I can't really play it right now, my girlfriend plays it on my PC (we live together). Will I be able to later reset my hours played and my achievements and start from scratch? I've read that disabling achievements will be a feature, but I don't know if that will reset them.
Thanks!

On Galaxy don't know,but under that other Steam Set up you just deleted game and installed
again.Stats were nil.

I'm pretty sure not even GOG knows what features Galaxy will have.
But I'm going to assume they've planned to attach the achievements to the logged in user account, so if your girlfriend plays using your account she will get you all the achievements.
But if you simply create a new account and login with said account to Galaxy and add W3, they will probably be tied to her account.
I doubt they'll add a reset button, but I'm sure they'll do it if you e-mail them.

Probably not, but I'm not sure what might happen if your girlfriend makes her own GOG account and logs in to that before playing, not sure if Galaxy will trigger the stuff for her if the game is not on her account instead of her playing with your account.

EDIT: Smannesman got there before me. xD

Where I'm from that grounds for murder, and there isn't a jury on the planet that would find you guilty! :P

Thanks for the help!

I realized too late that if she started playing it without Galaxy, just with the exe, the stats wouldn't have been tracked. Well, if by the time I start playing there won't be any option I'll contact support, see if they can help me.

2 years later and it seems like this is still not implemented, am I right? *Sigh*

well gog is just a big pile of shit nowdays. i don't expect anything from gog anymore, aside from more disappointments