I am on Windows 10 playing version 1.2.0. I switched off syncing to the cloud after I lost two days of play. Syncing, however keeps reactivating: I get the onscreen message "Syncing to the cloud." As soon as that happens the game reverts some cities to a state from a couple of weeks ago, while others retain the most recent changes. Today it also erased the last new city I built, 2/3 of my colonists, 2T in money and 5k starships. I am not amused.

When I checked the syncing state on the region map I found:

Clicking on Cloud Sync does nothing: it remains "On".
Clicking on Game Save Compression changes it form "Off" to "On", but at the same time Cloud Sync disappears:

Clicking Game Save Compression again switches it back to "Off," but Cloud Sync remains missing.

When I now open one of my cities and check compression and syncing I get:

and everything acts the same as for the region map. When I return to the region map form any of my cities it has reverted to the state in the first picture.