diff --git a/classes/models/coursework.php b/classes/models/coursework.php
index e06a8bf..7e8ecc1 100644
--- a/classes/models/coursework.php
+++ b/classes/models/coursework.php
@@ -1706,14 +1706,14 @@ public function get_student_group($student) {
 
         if ($this->grouping_id) {
                 $sql = "
-                SELECT groups.*
-                  FROM {groups} groups
+                SELECT g.*
+                  FROM {groups} g
             INNER JOIN {groupings_groups} groupings
-                    ON groups.id = groupings.groupid
+                    ON g.id = groupings.groupid
             INNER JOIN {groups_members} gm
-                    ON gm.groupid = groups.id
+                    ON gm.groupid = g.id
                  WHERE gm.userid = :userid
-                   AND groups.courseid = :courseid
+                   AND g.courseid = :courseid
                    AND groupings.groupingid = :grouping_id
 
                  LIMIT 1
@@ -1724,20 +1724,18 @@ public function get_student_group($student) {
                 'userid' => $student->id()];
         } else {
             $sql = "
-                SELECT groups.*
-                  FROM {groups} groups
+                SELECT g.*
+                  FROM {groups} g
             INNER JOIN {groups_members} gm
-                    ON gm.groupid = groups.id
+                    ON gm.groupid = g.id
                  WHERE gm.userid = :userid
-                   AND groups.courseid = :courseid
-                 LIMIT 1
-            ";
+                   AND g.courseid = :courseid
+                 LIMIT 1";
             $params = [
                 'userid' => $student->id(),
                 'courseid' => $this->get_course()->id,
             ];
         }
-
         $group = $DB->get_record_sql($sql, $params);
         return group::find($group);
 
@@ -2264,11 +2262,11 @@ public function get_allocatables() {
         if ($this->is_configured_to_have_group_submissions()) {
             if ($this->grouping_id) {
                 $sql = "
-                SELECT groups.*
-                  FROM {groups} groups
+                SELECT g.*
+                  FROM {groups} g
             INNER JOIN {groupings_groups} groupings
-                    ON groups.id = groupings.groupid
-                 WHERE groups.courseid = :courseid
+                    ON g.id = groupings.groupid
+                 WHERE g.courseid = :courseid
                    AND groupings.groupingid = :grouping_id
             ";
                 $params = [
@@ -2276,11 +2274,7 @@ public function get_allocatables() {
                     'courseid' => $this->get_course()->id,
                 ];
             } else {
-                $sql = "
-                SELECT groups.*
-                  FROM {groups} groups
-                 WHERE groups.courseid = :courseid
-            ";
+                $sql = "SELECT * FROM {groups} WHERE courseid = :courseid";
                 $params = [
                     'courseid' => $this->get_course()->id,
                 ];
diff --git a/classes/warnings.php b/classes/warnings.php
index 9a275e0..51aacfa 100644
--- a/classes/warnings.php
+++ b/classes/warnings.php
@@ -87,14 +87,14 @@ public function students_in_mutiple_grouos() {
                                  groupings.groupingid,
                                  u.firstname,
                                  u.lastname
-                           FROM {groups} groups
+                           FROM {groups} g
                      INNER JOIN {groups_members} gm
-                             ON groups.id = gm.groupid
+                             ON g.id = gm.groupid
                      INNER JOIN {groupings_groups} groupings
-                             ON groups.id=groupings.groupid
+                             ON g.id=groupings.groupid
                      INNER JOIN {user} u
                              ON u.id = gm.userid
-                          WHERE groups.courseid = :courseid
+                          WHERE g.courseid = :courseid
                             AND groupings.groupingid = :groupingid
                        GROUP BY gm.userid, groupings.groupingid, u.firstname, u.lastname)a
                           WHERE noofgroups > 1";
@@ -107,12 +107,12 @@ public function students_in_mutiple_grouos() {
                                    count(gm.userid) as noofgroups,
                                    u.firstname,
                                    u.lastname
-                              FROM {groups} groups
+                              FROM {groups} g
                         INNER JOIN {groups_members} gm
-                                ON gm.groupid = groups.id
+                                ON gm.groupid = g.id
                         INNER JOIN {user} u
                                 ON u.id = gm.userid
-                             WHERE groups.courseid = :courseid
+                             WHERE g.courseid = :courseid
                           GROUP BY gm.userid, u.firstname, u.lastname) a
                     WHERE noofgroups > 1";
 
@@ -132,13 +132,13 @@ public function students_in_mutiple_grouos() {
                     // Get group ids of these students
                     if ($this->coursework->grouping_id) {
 
-                        $sql = "SELECT groups.id,groups.name
-                               FROM {groups} groups
+                        $sql = "SELECT g.id, g.name
+                               FROM {groups} g
                          INNER JOIN {groupings_groups} groupings
-                                 ON groups.id = groupings.groupid
+                                 ON g.id = groupings.groupid
                          INNER JOIN {groups_members} gm
-                                 ON gm.groupid = groups.id
-                              WHERE groups.courseid = :courseid
+                                 ON gm.groupid = g.id
+                              WHERE g.courseid = :courseid
                                 AND gm.userid = :userid
                                 AND groupings.groupingid =:grouping_id";
 
@@ -148,11 +148,11 @@ public function students_in_mutiple_grouos() {
                             'userid' => $student->userid];
                     } else {
 
-                        $sql = "SELECT groups.id,groups.name
-                                FROM {groups} groups
+                        $sql = "SELECT g.id, g.name
+                                FROM {groups} g
                           INNER JOIN {groups_members} gm
-                                  ON gm.groupid = groups.id
-                               WHERE groups.courseid = :courseid
+                                  ON gm.groupid = g.id
+                               WHERE g.courseid = :courseid
 		                         AND gm.userid = :userid";
 
                         $params = [
diff --git a/lib.php b/lib.php
index 3f3e735..d754522 100644
--- a/lib.php
+++ b/lib.php
@@ -371,8 +371,9 @@ function coursework_grade_item_update($coursework, $grades = null) {
         throw new invalid_parameter_exception("Invalid type '$paramtype' for coursework");
     }
 
-    if (get_class($coursework) != 'mod_coursework\models\coursework') {
-        // On activity rename, core will pass in stdClass object here, not a coursework.
+    if (get_class($coursework) == 'stdClass') {
+        // On activity rename, core will pass in stdClass object here.
+        // Otherwise expect coursework or coursework_groups_decorator to be passed.
         $coursework = \mod_coursework\models\coursework::find($coursework);
     }
 
diff --git a/tests/behat/behat_mod_coursework.php b/tests/behat/behat_mod_coursework.php
index 7b32577..65dd4e1 100644
--- a/tests/behat/behat_mod_coursework.php
+++ b/tests/behat/behat_mod_coursework.php
@@ -299,17 +299,6 @@ private function get_first_assesor_stage() {
         return reset($stages);
     }
 
-    /**
-     *
-     *
-     * @param $rolename
-     * @return string
-     */
-    private function make_role_name_into_variable_name($rolename) {
-        $rolename = str_replace('other ', 'other_', $rolename);
-        return str_replace(' ', '', $rolename);
-    }
-
     /**
      * Returns an xpath string to find a tag that has a class and contains some text.
      *
@@ -1896,40 +1885,6 @@ public function there_is_some_general_feedback() {
         $this->get_coursework()->save();
     }
 
-    /**
-     * @Given /^(I|the ([\w ]+)) (?:has|have) graded the submission as assessor (\d+)$/
-     *
-     * @param $i
-     * @param string $rolename
-     * @param int $assessornumber
-     * @throws coding_exception
-     */
-    public function the_other_teacher_has_graded_the_submission($i, $rolename = '', $assessornumber = 1) {
-
-        if ($i == 'I') {
-            $rolename = 'teacher';
-        } else {
-            // other editing teacher => other_editingteacher
-            $rolename = $this->make_role_name_into_variable_name($rolename);
-        }
-
-        if (empty($this->$rolename)) {
-            throw new coding_exception('no ' . $rolename . ' user was found');
-        }
-
-        /**
-         * @var $generator mod_coursework_generator
-         */
-        $generator = testing_util::get_data_generator()->get_plugin_generator('mod_coursework');
-
-        $feedback = new stdClass();
-        $feedback->submissionid = $this->submission->id;
-        $feedback->assessorid = $this->$rolename->id;
-        $feedback->stage_identifier = 'assessor_'.$assessornumber;
-        $feedback->grade = 50;
-        $generator->create_feedback($feedback);
-    }
-
     /**
      * @Then /^I should( not)? see the other teacher\'s grade as assessor (\d+)$/
      * @param bool $negate
@@ -2756,8 +2711,7 @@ public function i_should_see_that_the_submission_was_made_by_the_other_student($
      * @throws coding_exception
      */
     public function i_am_logged_in_as_a($rolename) {
-
-        $rolename = $this->make_role_name_into_variable_name($rolename);
+        $rolename = str_replace(' ', '', $rolename);
 
         if (empty($this->$rolename)) {
             $this->$rolename = $this->create_user($rolename);
@@ -2826,8 +2780,13 @@ protected function create_user($rolename, $displayname = '') {
         $user = \mod_coursework\models\user::find($user);
         $user->password = 'user' . $this->usersuffix;
 
-        $roleid = $DB->get_field('role', 'id', ['shortname' => $rolename], MUST_EXIST);
+        // If the role name starts with 'other_' here (e.g. 'other_teacher') we need to remove it.
+        $rolename = str_replace('other_', '', $rolename);
+        $roleid = $DB->get_field('role', 'id', ['shortname' => $rolename]);
 
+        if (!$roleid) {
+            throw new coding_exception("Cannot find role shortname '$rolename' in role table");
+        }
         if (empty($this->course)) {
             throw new coding_exception('Must have a course to enrol the user onto');
         }