I recently had the problem of an application (DreamWeaver) which had hidden a Windows dialog box. When opening it, it was out of view. But how to drag it back? It appears that this is rather easy (if you know how).
First, you use your keyboard:
Ctl-Space to open the system menu of the dialog box. You don’t see anything, but you can hit
Enter to select the “Move” option of the menu. Your mouse pointer should have been brought to the dialog window.
Gently click on the left button and drag the window around, you have the window stuck and it should follow the mouse movements. This way, you can find and drag it back.