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Are there any special settings, which should be taken when starting the game?

The game keeps on crashing before the first mission starts, it just happens when trying to play the regular game, the expansion disk starts correctly.

Any ideas?

I have the same problem. As soon as the 'pda' opens , the screen shows some kind of machine code and shuts the game down.
I can play the '2' option as well. I know the map codes from playing way back, and I tried to use those in the menu while playing the expansion game , and that doesn't work either.
Also I tried to download the game through but after downloading the 2 gb file it unpacks in the folder on the C drive !
I have been able to play the regular battle isle game with install for a couple of weeks before it started crashing, so it seems there is some problem with the way the game loads its data (maybe with the cloud?)

Also I have uninstalled the game and all the saved data, before reinstalling everything, which didn't help either