Version mkgmap-r4379 was committed by gerd on Wed, 27 Nov 2019 fix NullPointerException when option --polygon-size-limits doesn't give a value for the resolution at level 1. Problem was introduced with r4376, which used 0 for those resolutions. This behviour seems strange but it restored now. http://www.mkgmap.org.uk/websvn/revision.php?repname=mkgmap&rev=4379