Sounds like a Windows configuration issue. The TD doesn't really do anything with the mouse pointer itself.
One thing to look at is how you have your extended display configured in Windows. Is the extended display to the left or right of the main display? If it's on the side you're not expecting, it may seem like the mouse pointer gets stuck on the other display. Right-click on the Windows desktop and select "Screen resolution" (when your extended display is connected). Click on each of the displays in the display diagram and look at the bottom of the settings where it tells you either "This is your main display" or "Make this my main display", based on which display you click. Your main display will have your Windows start menu and taskbar on it (this of course assumes Windows 7; Windows 8 might be different).