I'll kill a couple birds here with one stone. Solving a differential equation IS a process; it doesn't matter if you do it or a computer does. In fact, anything that can be expressed as an algorithm is a process and the act of execution does not require intelligence by definition.
One of the questions that no one has asked is "what is the definition of intelligence?". It is a very good question, and the handwaving popular definition is meaningless. Intelligence is a PROCESS with some specific properties that I won't bother going into here for the sake of brevity. Because it is a process, it is expressable as an algorithm. What this means is that intelligence itself is nothing more than a process expressable on any engine capable of computation (which is damn near every bit of matter in the universe). This topic is a book length discussion on mathematics; Springer-Verlag publishes a couple good ones that cover the relevant mathematics if you really want to learn this stuff.
Therefore, intelligent design is ultimately lame because it is trivially reduceable to "scientific naturalism" as you put it. At least creationism is derivative from a totally different (though arguable) premise. Note that "rules" have to exist in any system that hasn't decayed to perfect entropy. The exact nature of what we are calling rules here is essentially arbitrary, but they are an emergent property of any system that hasn't bottomed out to heat death.