Okay, regarding evolution and Altarians, that's in GalCiv materials. The Mithrilar and Draginol (the Mithrilar who was hanging out on Altar) are explained in links from this thread:
Altarians look like humans because Draginol ended up there and made them look like humans, I think through passive influence. There were also wars involving the Dread Lords and the Arnor, resulting in a cataclysm that broke the world a bit. The history in the Elemental games parallels events in GalCiv, although in much more detail. But even ignoring Elemental, GalCiv still establishes that Altarian evolution was tampered with to make them appear human. The Altarian History tech in TotA spells out that there were multiple races on Altaria in direct conflict with each other.
In Elemental, wraiths are pale bluish-skinned people that changed in some way due to a particular event involving their leader binding them to her through the use of magic. I haven't played the campaign so I do not know the specific details.
Brad already stated earlier in the thread that he would confirm or deny nothing. All that's left is to go over the histories and information presented in both games and see where they coincide - which is in multiple places. Mentions of characters such as Tandis and events such as the cataclysm, the parallels between the titans and the Dread Lords. Like:
http://www.elementalgame.com/fallen-enchantress/myths discusses Tandis directly.
Tandis is also, IIRC, the Arnor who gives terror star technology to the Terrans in Twilight of the Arnor. Plus, of course, Altarians can build the Shrine of Tandis.
In Twilight of the Arnor, you can find a lot of information about Altarian history and Altarian "magic" in the Altarian techtree.
So, I wouldn't swear that they're the same, but they seem similar enough and draw on enough common sources that I would hesitate to deny it.
As far as natural evolution goes, if humans can end up with blue skin due to genetics or colloidal silver, human-like beings can end up with blue skin without having drastically different biochemistry. It's not necessary for such a trait to have a specific purpose that lends itself to survival. It may simply not be sufficient to prevent survival.