I created an important bug fix version 1.3.2 for the plugin. Please update your 1.3.1 installation from the SVN branch:
http://svn.ilias.de/svn/ilias/branches/fau/plugins/assAccountingQuestion-1.3.x
This version fixes a bug in 1.3.1 that resulted in 0 points for the question when the points were recalculated by ILIAS after a test has been written (e.g. for adjusting the scoring options).