I wonder if it is related to either the drawing frame or the pen set associated with the drawing? Perhaps the drawing is there, but outside of the frame.
Did you try opening Drawing Settings for one of these external drawings and under the Frame panel, verifying that "Fit Frame to drawing" is selected?
Same dialog, under Properties, if the scale is right, is the Pen Set one which would have non-white pens for the drawing elements?
Karl
One of the forum moderators
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