First problem I had was Galaxy wouldn't update. I'd get the message when starting that there was an update but then it would fail. I'd start Galaxy again and it was fine, just an older version.
If I clicked on "check for update" within Galaxy the update would fail again. I uninstalled Galaxy and reinstalled and the update worked. Until a new update was released. Same issue. I reported this problem to Gog twice, once in December and again a couple of days ago. Never heard anything.
I tried reinstalling Galaxy again and now it won't even start. I went to the website and downloaded a couple of game installers and they won't even start.
Games through Steam, Ubisoft. Epic, all work fine.