Do creationists believe in microevolution?Creationists claim to accept microevolution, but not macroevolution. These are convenient beliefs because microevolution takes place over short time spans (perhaps thousands of years) and is amenable to (relatively) direct scientific scrutiny. Macroevolution, on the other hand, is a long term process (millions of years) and hence more difficult to study and evidence is more abstract.
Despite claiming to accept microevolution, creationists delight in refuting it. The best example is Jonathan Wells' Icons of Evolution which argues against microevolution of the peppered moth. Wells argues that in many cases correlation between tree trunk color and moth color was poor. Scientists have never claimed that "simple camouflage" was the only factor influencing peppered moth evolution. Wells expresses objections to "unnatural" experimental methods such as predation studies using dead moths glued to tree trunks. Such techniques are necessary in ecological studies because live moths are hard to find and don't keep still. Quantitative studies on predation of live moths require vastly more observation. Though clearly one must be cautious about "artificial" techniques, Wells' overly literal interpretation of evidence and disdain for the technology indicate little understanding of the practicalities of ecology.
Wells also has difficulties with the practicalities of the Grants' studies of Darwin's finches. The Grants demonstrated morphological changes in finches in response to prolonged drought. The Grants (Peter and Rosemary) extrapolated (extrapolations are always uncertain) what might have happened had the drought continued. In reality the drought ended and selection pressures changed. Wells claims that evolution did not occur since the changes did not persist. Wells is again overly literal. Perhaps he has confused evolution with speciation, as creationsts are wont to do. In point of fact, young earth creationists take delight in Wells' claim since they argue that Darwin's finches are all one "kind" which evolved from the created kind over the past 10,000 years.
Evidence suggests that creationists condemn evolution indiscriminately. They have no interest in science. Their concern is protecting (their specific) literal interpretation of Genesis 1 from potential objections.