the rectangles, which are popup windows, are placed according to the position of the main window as on the example
the number of rectangles can be changed with the keyboard: keys '1' to '0', and '+' and '-' key on the numerical pad (the number of rectangles can be limited, in other words for some number of rectangles pressing the '+' key can have no result)
the way the rectangles are placed can be changed by holding the 'Ctrl' key and moving the mouse within the client area of the main window
changing the position and sizes of the rectangles should be possible when either the main window or any of the popup windows is active
the rectangles should move and resize appropriately while moving and sizing the main window
The main window:
moveable and sizeable
Popup windows:
features:
not sizeable
always on top
not visible on the taskbar
background color - system color for inactive window's caption