I'm happy to report that we now have version 1.0.4 of the iWP software, hence the spacing between the paragraphs can be preserved. There was apparently a problem in the IE (Internet Explorer) browser's handling of rich-text that causes this strange problem; it's now been worked around.

 

All articles uploaded from now on will have the preserved spacing. The editors will soon update the other, previous articles to add in the missing spaces.