reading the book starkiller starts off with all stock factory parts. no aftermarket cybernetics. we're thinking that the armor plates were pulled off a droid (don't have ay idea what type though), and it already had the restraining bolt attached. check the scoring pattern under it, very similar to what r2 had after the jawas put the bolt on him.
as far as controlling starkiller, vader taught him to be a force wrecking ball. there is no subtlty to his control. philosophical thinking would put most of yoda's younglings more adept in the ways of the force. vader could manipulate him very easily through the force if he couldn't control him psychologically the way palpatine controlled anakin.
