The game seems to consistently crash, if some other Programm tries to establish an internet Connection eg for accessing an update site and is asking if it should go ahead with it.
The problem starts with an Windows error message "DIV..." (sorry, klicked the message away before I realized that it would crash the game.) Then the game says good bye.
In this case the Trigger was the Apple update Service for iTunes, etc. which popped up. When I okayed the update, the game crashed after the "DIV..." message was shown. The update for Apple was successful, so the error must have been triggered by the game.