cofty: Any naturalistic answer that works proves that supernatural answers are unnecessary.
shadow: The arch example does not prove that God did not do it.
Shadow, there is a big difference between saying "this shows God is unnecessary as an explanation" vs saying "this proves God could not be the explanation."
We have millions/billions of confirmed (repeatable) examples of natural explanations for phenomena, and precisely zero supernatural explanations for any phenomena. This alone is enough to say that a plausible naturalistic explanation for any one phenomenon is sufficient to render a supernatural explanation extraneous and unnecessary. (That's a long-winded way of saying "Ockham's Razor FTW!")
As Viviane said, the article you posted lists problems with a number of ideas about the evolutionary reason for our loss of fur, but even if those problems are insurmountable by proponents of those various ideas, it still leaves the 12th idea, from the article you quote approvingly, as a valid explanation. So, rather than undermining evolution, you've only undermined the thermoregulatory theory of fur-loss and helped establish the some-other-theory theory of fur-loss.
What you need to do is show that there is no possible evolutionary explanation for humans losing their fur--that the only possible explanation is a supernatural one. If you can't do that, then you've only changed the status of the question from "Probably because X" to "unknown (for now)."
Edit: In other words, what 2+2=5 said.