Hello Javca,
I have fixed this issue on your site, the following files are modified:
administrator/components/com_jajobboard/views/jacategories/view.html.php
administrator/components/com_jajobboard/views/jacategories/tmpl/default.php
administrator/components/com_jajobboard/views/jalocation/view.html.php
administrator/components/com_jajobboard/views/jalocation/tmpl/default.php
FYI: for sorting order, you need click save button first (save icon on ordering column), it will assign order number for categories/locations. Then you can use up/down arrow to change order of one category/location.