God is a postulate. He can't really be tested for or proven. And postulates have their place in scientific theories.
Postulates have only a value in science if used to prove a thesis under certain assumptions. (e.g. "If P=NP, than breaking RSA is easy"). Unfortunately, the existance of a God does not prove ID in the slightest. I don't see any reason why a God should take the stupid task do design all species one by one. (The non-existance of a God, however, would disprove ID.)
Everyone has the right to individually decide if they believe in a Creator or not. But flatly denying that it is even a possiblity is as much as an unfounded leath of faith as flatly denying he must exist.
Evolution does not per se deny the existance of a Creator. If you want to couple evolution with the belief of a creator, just imagine a Creator that made the rules, and said rules resulted in all the life forms we see today. Even the Pope acknowledges evolution, and I'm pretty sure he firmly believes in a Creator...
The proper scientific approach is to suggest it could be valid as a theory, but can't be tested at this time. Suggesting otherwise is zealoty all the same.
It can not only "not be tested at this time", it can't ever be tested. It is also not a theory. (Wikipedia: "The word theory, when used by scientists, refers to an explanation of reality that has been thoroughly tested so that most scientists agree on it. It can be changed if new information is found.") It's not even a hypothesis, because it is not testable. Suggesting otherwise is a grave misunderstanding of the scientific approach.