who; is spiritual
when; is the position of the act of creation in the sequence of the other acts of creation
how; is the way it is decided
explanation for fossils: from an act of creation there is a beginning middle and end. Obviously the fossil is at the end.
the reason people are similar to chimps: because it's kind of funny to have creatures similar yet different, that's a good reason. Meaning creationists find the reason in the future, instead of the past. So if for instance there would be no contact at all between chimps and people, then there would be no reason why chimps and humans are similar. So basically creationism is focused on real relationships between things, rather then platonic relationships between things.
the unit of design: The classes of organisms were likely to be from the beginning of the universe, including the class of human beings. The rest was designed later. In any case to do intelligent design theory, you should trace back the likelyhood of the organism / species coming to be to zero. Along the way you will find all decisions that made it what it is.