The tracking area for both the arm and the tablet is defined by the Spud Arm window, so to have everything work correctly, you'll want to have the Spud Arm window fullscreened or maximized behind your drawing software.
The Spud Tablet window stays a fixed size to make it easier to keep it properly aligned in your stream layout.
The hands are intentionally set up to disappear when the cursor goes too far outside of the tracking area - without this, some strange things could potentially happen when you need to use your cursor on a different monitor.