Please repost the problems you are having with the scenarios in the appropriate subforum. This is not limited to scenarios, but rather is a problem with the AI in general. When at war, the AI focuses too heavily on its military and so does not develop. If war occurs too early for the AI to have developed a stable economy, or if a war breaks out and peace never comes, then the AI will stagnate. This situation makes the scenarios which start off in a war state unplayable right now, because the AI never gets to do the "peacetime development" that it needs to do in order to compete.