For the touch screen: next release (coming soon) is better.
For your additional pixels, on the corner... I never saw that, but it looks like a reflexion (it seems that there is no missing pixels on the icon!).
For the button, it seems that, for some Primers, the button is not perflectly centered (on the next production, the button as a centering finger that solves this issue). The only thing to do is to open it and, with a knife, to scrape the plastic of the plastic case (inside the square hole).
For the sound, the welcome message had been recorded on a PC. We didn't spend too much time on the quality of the recorded sound... perhaps settings of the STw5094A could be improved/