This message appears if the value entered in the height or width box in the Frame Options or Frame Properties dialog is not a number.
This message appears if the size entered in the Size Box in the Frame Options or Frame Properties dialog is below 5mm or above 500mm, or is not a number. The Size setting refers to the height in millimeters of the selected Frame. If you wish to increase the size above this you could drag one of the corner boxes or alter the Height or Width proportions.
This message appears if the size entered in the Margin box on the Frame window of the Control Panel is below -50mm or above 50mm.