If the windows taskbar is on the left hand side or along the top of the screen, the screen grid is offset by the width/height of the taskbar, making the numbers incorrect.
E.g., mine is on the left, which I find much better on widescreen displays, and the displayed screen grid starts at 1 at the right edge of the Windows taskbar, which in reality is where the mouse pointer ends up if I say “move mouse 5 at 1”. The right edge of the screen grid is also visible on my second monitor off to the right, the same width as my windows taskbar ,so in effect the entire grid displays shifted over by the width of the taskbar.
Whilst on the topic, can we not include zero in the possible mouse coordinates? e.g. I’d like to say “move mouse 30 at zero” to put it at the very top, but it will only accept 30 at one.