Try editing the icon you use to start Poser. Right click on it and go to properties. A new dialog box will appear with some tabs at the top. Click on the shortcut tab and you will have some text boxes below. Look for the run section. See if "normal window" appears or not. If not, selct it by clicking on the down arrow. If it is there, you may have to resort to manually changing it from maximized to windowed.