Hopefully you have learned a reasonable amount about the genomes of various primates, and so will be able to answer this question.

When we search the genome of the various primates, why do we see no evidence of this genetic engineering? If we look at functional redundancy in our proteins, for example, we see no evidence of a step-change in any coding that would be suggestive of your theory. Rather, we see the rate and number of mutations that the theory of evolution would predict. We get branching points and family trees that match those implied by morphology, for example.

As to your questions about issues such as standing upright, well, what are your own thoughts on why that may have happened? Do you know that it apparently took only around 10,000 years for modern Europeans to become white after they left africa?

It can happen even faster, I understand; the aboriginal inhabitants of the USA had darker skin only a few hundred years ago, yet I now commonly meet people from there who claim to be "true" americans yet who are even paler than my Northern European self...