Thanks to the help of players sending reports i managed to find a serious crash which is also corrupting save files (happens during saves)
Im trying to find a way to restore the corrupted files, but most of the ones i received are beyond repair. In any case a fix so that the problem does not happens again will be online today.
Im really sorry to all players that lost their files and ask that those who didn't wait until the fix is online before they resume playing.