There seems to be an issue with Rise to Ruins in the last few days, and appears to be something on Valve's end and out of my control. It is causing user's save data to be corrupted when they save and exit the game. It appears Steam Cloud is erroneously syncing corrupted data for some players.
In the mean time, I have disabled Auto-Cloud on my end within Steamworks, but it does not appear to be solving the problem for everybody. I strongly suggest you should disable Cloud Saving for Rise to Ruins and restart your client just to be safe.
1) In your Steam Library, right-click on Rise to Ruins and select "Properties."
2) Click the "Updates" tab.
3) Uncheck "Enable Steam Cloud synchronization for Rise to Ruins."
4) Click "Close."
5) Restart Steam.
Sorry in advance for anyone who loses their data! Hopefully this issue will be resolved as fast as possible. But disabling Steam Cloud should protect you. :)