@Gargantua Right. The issues are already addressed:
and have been analyzed by the developers here:
As far as I have understood the problems occur when not all players are on the most current stable version. Once a game is either started with an older release or a savegame started with the current version is opened with an older version the games are somehow corrupted.
This is why I have added the following note to some of the stickies here:
Problems in games started in the past cannot be resolved by updating the TripleA client, as updating the client does not change the game information stored in savegame files. In other words: As long as nobody starts new games with up-to-date clients and maps, the problems, saved in savegame-files, will be carried over and continue.
Also: To avoid issues it is always recommended that all players use the latest stable version to beginn new games. So when playing together, reassure yourself that everyone is up-to date.