Created attachment 93276 [details]
Sample that shows how the polylines get expanded

I am enclosing an odt file where I created a collage of shapes that looks like a paint roller. 

However, if I save and close the file, only the POLYLINE components of this collage get disturbed. The collage no longer looks like a roller.

Just for reference, I converted the original file to pdf, to preserve the original shape, which gives you an idea.

To repeat the experiment, just resize the polylines ("wires" of the roller) horizontally and vertically.

I have noticed a pattern: In both shapes, I have to grab the 3-o'clock and 6-o'clock handles and drag till the shape gets restored perfectly. 
* You don't have to move the other handles. 
* You also don't have to move the entire shapes.
* Only polylines affected this way: The square shapes are NOT affected.