We were advised of a critical bug which causes save files to become corrupted.
Unfortunately the bug is not yet able to be replicated, however it may be related to one of the bugs fixed in the previous release.
We are actively trying to replicate the bug at the moment.
For the time being we have added more logging to the save process, and are creating a backup of the game save files before starting the save process.
If the issue does occur moving forward we can obtain more details for a fix.
The backup will prevent a complete lose of saved progress, and you can restore this backup from your systems application data directory.
We are very sorry if you have encountered this issue.