Good grief! There are different number of chromosomes in MANY humans TODAY (such as in Downs or Klienfelter's syndromes). The issue is not whether differing numbers of chromosome pairs occur. It is whether it is possible to propagate an extrachromosomal or subchromosomal genotype and thereby create a new species.
Thank you for demonstrating that you in fact do not understand the topic.
So then, unlike most skeptics of evolution, you do NOT accept that the various members of the horse family (for instance) share a common ancestry by reproductive descent, since the species have wildly differing chromosome numbers?
You realize that this would make you an extremist and deviant even among the strictest creationists, who usually take offense if they are stereotyped as holding to the 18th-19th Century notion of fixed species?