I am sad to report that cloud saves are completely broken on Parkitect.
GoG Galaxy appears to be uploading something after you close the game, but when manually checking the "Cloud Backup" in extras, its not being updated.
When installing the game on another machine it doesn't download the cloud backup, even if it does, it's empty.
Now I am stuck manually copying the saves or using 3rd party apps like GSM or one drive sync. I want to support GoG and indie developers but this is kind of BS driving me away.
And yes I play & work on 4 machines through the day, so I do need this.