Since Steam is a direct competitor to Impulse, I'd say that the chances they will intentional support of the Steam Overlay and take time to make sure it works are in the 0-1% range.
That's not to say Elemental won't work with Steam overlay, but I seriously doubt Stardock will put even a single thought into making sure it's compatable.
Now, if I were Frogboy[e digicons]:frogboy:[/e] , I would intentially make sure Elemental does NOT work with any aspect of Steam, but that's just me[e digicons]
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