Hello van der Merwe.
I can normally play the game for a few hours before it CTD, on the Steam version. If this is what you are getting then there isn't much that you can do about it I'm sorry to say.
Just save the mission your playing every 10 minutes then you can re-load it, when the game CTD.
Went and where is the game crashing?
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Britannia Rule Waves (Yet right not now

) and Who Dares Wins
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