I have to say I don't know enough about it to have an opinion on this. But there is something about her demeanour that really makes me squirm. That doesn't make her guilty though.

I take a completely different view. The evidence against Knox and Sollecito was so flimsy as to be non-existent. Knox was "interviewed" for hours and hours with no lawyer present and made a "confession" which was so obviously false (the result of bullying/brainwashing) that not a scrap of evidence could be found to support it. The real villain (apart from the murderer Rudy Guede) was the insane Italian prosecutor who was obsessed (and not only in this case) with notions of satanic sexual depravity and who was determined (irrespective of the facts) to pin it on Knox. Unfortunately, Meredith Kercher's family was taken in by this nutter's fantasies, and have clung to the view that Knox was guilty throughout - an evidence-free view!
I don't think that nationality, money or political pressure have been issues here - just evidence and its conspicuous lack.