It seems to run fine on my Mac and I've figured out most of what the numeric keypad does, but due to the lack of that Macintosh's provision for extensive keyboard navigation (some functions are only available by using the mouse) the interface is rather difficult to navigate with a screenreader. With this in mind, the screenreader allows the user to use the mouse to examine the screen contents and it will read out items on the screen when the mouse passes over them, but using a mouse without the feedback of seeing the mouse pointer on the screen is practically impossible. Nevertheless it is an interesting concept, but I don't think that using a screenreader on my Mac will really be practical.