1) How do you make the magnifier to stay on a fixed point of the text?
As is when you magnify a page the cursor position changes with respect to the text. But for a visually imapired person it would be hard to navigate to particular place in text if his/her position is changed. Such a person can get easily lost.
2) Is there a way of assigning a color to the scroll bar?
The scroll bars of the Reader are dark gray in a light grey background. After magnification this bar could get small and hard to detect for a visually impaierd person. Choice of color is also imortant for color blind person.