Another question I have is why CTD seems to fixate his questions on hand and foot bones. What makes you think that a) it is crucial to have these in order to work out the probability of the organism being bipedal; and b) that none exist? Or that certain crucial ones (please define) don't exist?

You can read here about hominid fossils, including information about how the leg bones and pelvis can tell us about bipedal locomotion. Here is a picture of the pelvises and leg bones of a chimpanzee, Australopithecus africanus, and a modern human. And also their feet. It is undeniable that africanus resembles the modern human bones. The fossil called Lucy is an australopithecus.

To further satisfy your curiosity on the subject, here is an article titled Fossils, Feet and the Evolution of Human Bipedal Locomotion. I learned a lot from reading it and I'm sure you will too.

Now, will you answer my questions?