Von Moltke fully expected Italy to attack France in the South. The Schleiffen plan (or his modification of it) assumed not only this, but that Belgium would surrender without a fight, and that British armies would arrive to late or in too small numbers to count.
You could, of course, interpret this as evidence that Italy never had any intention of attacking. But the majority in the Italian cabinet were in favour of at least neutrality right up to signing the treaty with the Allies in April 1915.
Until then, there was in effect a bidding war between the two alliances for Italian support.
I still maintain that Italy joining the Allies in Spring 1915 was by no means inevitable, and that if the CP had either conquered more of France, or offered more in bribes, Italy might have gone the other way or at least remained neutral.
Ideally, if things go exactly as they did historically up to Spring 1915, then Italy should join the Allies. But then, if that’s the case in every game, it’s not really a game, now is it?
http://www.guildofblades.com/WWI_semi_historical.php
http://en.wikipedia.org/wiki/Italy_in_WWI#From_neutrality_to_the_intervention_in_the_war