Notices on Specimen assessment form, workshop module

After creating a new exercise with all the default settings and 1 exercise elements, when I access the "speciment assessment form", I get the following notices:

Notice: Trying to get property of non-object in D:\VertrigoServ\www\moodle_19\mod\exercise\locallib.php on line 1572
Call Stack
#Time Memory Function Location
10.0203 516920

{main}( ) ..(null):0
20.8682 15848824 exercise_print_assessment_form( ) ..(null):254

( ! ) Notice: Trying to get property of non-object in D:\VertrigoServ\www\moodle_19\mod\exercise\locallib.php on line 2007
Call Stack
# Time Memory Function Location
1 0.0203 516920 {main}

( ) ..(null):0
2 0.8682 15848824 exercise_print_assessment_form( ) ..(null):254

( ! ) Notice: Trying to get property of non-object in D:\VertrigoServ\www\moodle_19\mod\exercise\locallib.php on line 2010
Call Stack

1. Time Memory Function Location
   1 0.0203 516920 {main}

   ( ) ..(null):0
   2 0.8682 15848824 exercise_print_assessment_form( ) ..(null):254