diff --git a/src/components/FilePreview/FileCard.jsx b/src/components/FilePreview/FileCard.jsx
index 27db0aa..1643d40 100644
--- a/src/components/FilePreview/FileCard.jsx
+++ b/src/components/FilePreview/FileCard.jsx
@@ -12,7 +12,7 @@ import './FileCard.scss';
  */
 export const FileCard = ({ file, children }) => (
   <Card className="file-card" key={file.name}>
-    <Collapsible className="file-collapsible" defaultOpen title={<h3>{file.name}</h3>}>
+    <Collapsible className="file-collapsible" defaultOpen title={<h3 className="file-card-title">{file.name}</h3>}>
       <div className="preview-panel">
         <FileInfo><FilePopoverContent {...file} /></FileInfo>
         {children}
diff --git a/src/components/FilePreview/FileCard.scss b/src/components/FilePreview/FileCard.scss
index d82fce5..a515b59 100644
--- a/src/components/FilePreview/FileCard.scss
+++ b/src/components/FilePreview/FileCard.scss
@@ -2,6 +2,12 @@
 
 .file-card {
   margin: map-get($spacers, 1) 0;
+
+  .file-card-title {
+    text-overflow: ellipsis;
+    white-space: nowrap;
+    overflow: hidden;
+  }
 }
 
 .image-renderer {
@@ -18,4 +24,10 @@
 
 .txt-renderer {
   white-space: pre-wrap;
+}
+
+@include media-breakpoint-down(sm) {
+  .file-card-title {
+    width: map-get($container-max-widths, "sm")/2;
+  }
 }
\ No newline at end of file
diff --git a/src/components/FilePreview/FileCard.test.jsx b/src/components/FilePreview/FileCard.test.jsx
index e7ef285..d25e97c 100644
--- a/src/components/FilePreview/FileCard.test.jsx
+++ b/src/components/FilePreview/FileCard.test.jsx
@@ -29,7 +29,7 @@ describe('File Preview Card component', () => {
   describe('Component', () => {
     test('collapsible title is name header', () => {
       const title = el.find(Collapsible).prop('title');
-      expect(title).toEqual(<h3>{props.file.name}</h3>);
+      expect(title).toEqual(<h3 className="file-card-title">{props.file.name}</h3>);
     });
     test('forwards children into preview-panel', () => {
       const previewPanelChildren = el.find('.preview-panel').children();
diff --git a/src/components/FilePreview/__snapshots__/FileCard.test.jsx.snap b/src/components/FilePreview/__snapshots__/FileCard.test.jsx.snap
index b53a30b..a3d0d85 100644
--- a/src/components/FilePreview/__snapshots__/FileCard.test.jsx.snap
+++ b/src/components/FilePreview/__snapshots__/FileCard.test.jsx.snap
@@ -9,7 +9,9 @@ exports[`File Preview Card component snapshot 1`] = `
     className="file-collapsible"
     defaultOpen={true}
     title={
-      <h3>
+      <h3
+        className="file-card-title"
+      >
         test-file-name.pdf
       </h3>
     }
diff --git a/src/containers/CriterionContainer/CriterionFeedback.jsx b/src/containers/CriterionContainer/CriterionFeedback.jsx
index 07a1740..10035b6 100644
--- a/src/containers/CriterionContainer/CriterionFeedback.jsx
+++ b/src/containers/CriterionContainer/CriterionFeedback.jsx
@@ -25,6 +25,15 @@ export class CriterionFeedback extends React.Component {
     });
   }
 
+  get commentMessage() {
+    const { config, isGrading } = this.props;
+    let commentMessage = this.translate(isGrading ? messages.addComments : messages.comments);
+    if (config === feedbackRequirement.optional) {
+      commentMessage += ` ${this.translate(messages.optional)}`;
+    }
+    return commentMessage;
+  }
+
   translate = (msg) => this.props.intl.formatMessage(msg);
 
   render() {
@@ -42,9 +51,7 @@ export class CriterionFeedback extends React.Component {
         <Form.Control
           as="input"
           className="criterion-feedback feedback-input"
-          floatingLabel={this.translate(
-            isGrading ? messages.addComments : messages.comments,
-          )}
+          floatingLabel={this.commentMessage}
           value={value}
           onChange={this.onChange}
           disabled={!isGrading}
diff --git a/src/containers/CriterionContainer/CriterionFeedback.test.jsx b/src/containers/CriterionContainer/CriterionFeedback.test.jsx
index e13ab8c..7798e9a 100644
--- a/src/containers/CriterionContainer/CriterionFeedback.test.jsx
+++ b/src/containers/CriterionContainer/CriterionFeedback.test.jsx
@@ -12,6 +12,7 @@ import {
   mapStateToProps,
   mapDispatchToProps,
 } from './CriterionFeedback';
+import messages from './messages';
 
 jest.mock('data/redux/app/selectors', () => ({
   rubric: {
@@ -27,7 +28,9 @@ jest.mock('data/redux/grading/selectors', () => ({
     })),
   },
   validation: {
-    criterionFeedbackIsInvalid: jest.fn((...args) => ({ selectedFeedbackIsInvalid: args })),
+    criterionFeedbackIsInvalid: jest.fn((...args) => ({
+      selectedFeedbackIsInvalid: args,
+    })),
   },
 }));
 
@@ -67,11 +70,13 @@ describe('Criterion Feedback', () => {
       expect(el.instance().render()).toMatchSnapshot();
     });
 
-    test('is configure to disabled', () => {
-      el.setProps({
-        config: feedbackRequirement.disabled,
+    Object.values(feedbackRequirement).forEach((requirement) => {
+      test(`feedback is configured to ${requirement}`, () => {
+        el.setProps({
+          config: requirement,
+        });
+        expect(el.instance().render()).toMatchSnapshot();
       });
-      expect(el.instance().render()).toMatchSnapshot();
     });
   });
 
@@ -121,6 +126,40 @@ describe('Criterion Feedback', () => {
         expect(props.setValue).toBeCalledTimes(1);
       });
     });
+
+    describe('getter commentMessage', () => {
+      test('is grading', () => {
+        el.setProps({ config: feedbackRequirement.optional, isGrading: true });
+        expect(el.instance().commentMessage).toContain(
+          messages.optional.defaultMessage,
+        );
+
+        el.setProps({ config: feedbackRequirement.required });
+        expect(el.instance().commentMessage).not.toContain(
+          messages.optional.defaultMessage,
+        );
+
+        expect(el.instance().commentMessage).toContain(
+          messages.addComments.defaultMessage,
+        );
+      });
+
+      test('is not grading', () => {
+        el.setProps({ config: feedbackRequirement.optional, isGrading: false });
+        expect(el.instance().commentMessage).toContain(
+          messages.optional.defaultMessage,
+        );
+
+        el.setProps({ config: feedbackRequirement.required });
+        expect(el.instance().commentMessage).not.toContain(
+          messages.optional.defaultMessage,
+        );
+
+        expect(el.instance().commentMessage).toContain(
+          messages.comments.defaultMessage,
+        );
+      });
+    });
   });
 
   describe('mapStateToProps', () => {
@@ -142,7 +181,10 @@ describe('Criterion Feedback', () => {
     });
     test('selector.grading.validation.criterionFeedbackIsInvalid', () => {
       expect(mapped.isInvalid).toEqual(
-        selectors.grading.validation.criterionFeedbackIsInvalid(testState, ownProps),
+        selectors.grading.validation.criterionFeedbackIsInvalid(
+          testState,
+          ownProps,
+        ),
       );
     });
   });
diff --git a/src/containers/CriterionContainer/__snapshots__/CriterionFeedback.test.jsx.snap b/src/containers/CriterionContainer/__snapshots__/CriterionFeedback.test.jsx.snap
index 2858652..c22e932 100644
--- a/src/containers/CriterionContainer/__snapshots__/CriterionFeedback.test.jsx.snap
+++ b/src/containers/CriterionContainer/__snapshots__/CriterionFeedback.test.jsx.snap
@@ -1,5 +1,33 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`Criterion Feedback snapshot feedback is configured to disabled 1`] = `null`;
+
+exports[`Criterion Feedback snapshot feedback is configured to optional 1`] = `
+<Form.Group>
+  <Form.Control
+    as="input"
+    className="criterion-feedback feedback-input"
+    disabled={false}
+    floatingLabel="Add comments (Optional)"
+    onChange={[MockFunction this.onChange]}
+    value="criterion value"
+  />
+</Form.Group>
+`;
+
+exports[`Criterion Feedback snapshot feedback is configured to required 1`] = `
+<Form.Group>
+  <Form.Control
+    as="input"
+    className="criterion-feedback feedback-input"
+    disabled={false}
+    floatingLabel="Add comments"
+    onChange={[MockFunction this.onChange]}
+    value="criterion value"
+  />
+</Form.Group>
+`;
+
 exports[`Criterion Feedback snapshot feedback value is invalid 1`] = `
 <Form.Group>
   <Form.Control
@@ -19,8 +47,6 @@ exports[`Criterion Feedback snapshot feedback value is invalid 1`] = `
 </Form.Group>
 `;
 
-exports[`Criterion Feedback snapshot is configure to disabled 1`] = `null`;
-
 exports[`Criterion Feedback snapshot is graded 1`] = `
 <Form.Group>
   <Form.Control
diff --git a/src/containers/CriterionContainer/messages.js b/src/containers/CriterionContainer/messages.js
index d44e7aa..b7a014c 100644
--- a/src/containers/CriterionContainer/messages.js
+++ b/src/containers/CriterionContainer/messages.js
@@ -11,6 +11,11 @@ const messages = defineMessages({
     defaultMessage: 'Comments',
     description: 'label for read-only feedback field',
   },
+  optional: {
+    id: 'ora-grading.CriterionFeedback.optional',
+    defaultMessage: '(Optional)',
+    description: 'addtional label for optional feedback field',
+  },
   optionPoints: {
     id: 'ora-grading.RadioCriterion.optionPoints',
     defaultMessage: '{points} points',
diff --git a/src/containers/ResponseDisplay/ResponseDisplay.scss b/src/containers/ResponseDisplay/ResponseDisplay.scss
index 39d9f98..3f9b5ad 100644
--- a/src/containers/ResponseDisplay/ResponseDisplay.scss
+++ b/src/containers/ResponseDisplay/ResponseDisplay.scss
@@ -47,6 +47,10 @@
 
 @include media-breakpoint-down(sm) {
   .response-display {
-    min-width: 100vw;
+    width: 100%;
+
+    .preview-display {
+      padding: map-get($spacers, 1) 0;
+    }
   }
 }
\ No newline at end of file
diff --git a/src/containers/ReviewModal/ReviewContent.jsx b/src/containers/ReviewModal/ReviewContent.jsx
index a7e5aa0..b444236 100644
--- a/src/containers/ReviewModal/ReviewContent.jsx
+++ b/src/containers/ReviewModal/ReviewContent.jsx
@@ -15,15 +15,19 @@ import ReviewErrors from './ReviewErrors';
  * <ReviewContent />
  */
 export const ReviewContent = ({ isFailed, isLoaded, showRubric }) => (isLoaded || isFailed) && (
-  <div className="content-block">
+<div className="content-block">
+  <div className="content-wrapper">
     <ReviewErrors />
-    { isLoaded && (
-      <Row className="flex-nowrap">
-        <Col><ResponseDisplay /></Col>
-        { showRubric && <Rubric /> }
-      </Row>
+    {isLoaded && (
+    <Row className="flex-nowrap m-0">
+      <Col className="p-0">
+        <ResponseDisplay />
+      </Col>
+      {showRubric && <Rubric />}
+    </Row>
     )}
   </div>
+</div>
 );
 ReviewContent.defaultProps = {
   isFailed: false,
@@ -37,8 +41,12 @@ ReviewContent.propTypes = {
 };
 
 export const mapStateToProps = (state) => ({
-  isFailed: selectors.requests.isFailed(state, { requestKey: RequestKeys.fetchSubmission }),
-  isLoaded: selectors.requests.isCompleted(state, { requestKey: RequestKeys.fetchSubmission }),
+  isFailed: selectors.requests.isFailed(state, {
+    requestKey: RequestKeys.fetchSubmission,
+  }),
+  isLoaded: selectors.requests.isCompleted(state, {
+    requestKey: RequestKeys.fetchSubmission,
+  }),
   showRubric: selectors.app.showRubric(state),
 });
 
diff --git a/src/containers/ReviewModal/ReviewModal.scss b/src/containers/ReviewModal/ReviewModal.scss
index f09d319..8b0fec8 100644
--- a/src/containers/ReviewModal/ReviewModal.scss
+++ b/src/containers/ReviewModal/ReviewModal.scss
@@ -17,15 +17,27 @@
     margin: auto;
     height: 100%;
   }
+
+  .content-wrapper {
+    width: min-content;
+  }
 }
 
 @include media-breakpoint-down(sm) {
   .review-modal-body {
     padding: 0 !important;
-    overflow-y: hidden !important;
+    overflow: hidden !important;
+
+    & > div.pgn__modal-body-content {
+      overflow-y: scroll;
+    }
 
     .content-block .col {
       padding: 0;
     }
+
+    .content-wrapper {
+      width: 100%;
+    }
   }
 }
\ No newline at end of file
diff --git a/src/containers/ReviewModal/__snapshots__/ReviewContent.test.jsx.snap b/src/containers/ReviewModal/__snapshots__/ReviewContent.test.jsx.snap
index 40b1883..4a57d2b 100644
--- a/src/containers/ReviewModal/__snapshots__/ReviewContent.test.jsx.snap
+++ b/src/containers/ReviewModal/__snapshots__/ReviewContent.test.jsx.snap
@@ -4,7 +4,11 @@ exports[`ReviewContent component component render tests snapshot: failed, showRu
 <div
   className="content-block"
 >
-  <ReviewErrors />
+  <div
+    className="content-wrapper"
+  >
+    <ReviewErrors />
+  </div>
 </div>
 `;
 
@@ -12,15 +16,21 @@ exports[`ReviewContent component component render tests snapshot: hide rubric 1`
 <div
   className="content-block"
 >
-  <ReviewErrors />
-  <Row
-    className="flex-nowrap"
+  <div
+    className="content-wrapper"
   >
-    <Col>
-      <ResponseDisplay />
-    </Col>
-    <Rubric />
-  </Row>
+    <ReviewErrors />
+    <Row
+      className="flex-nowrap m-0"
+    >
+      <Col
+        className="p-0"
+      >
+        <ResponseDisplay />
+      </Col>
+      <Rubric />
+    </Row>
+  </div>
 </div>
 `;
 
@@ -28,13 +38,19 @@ exports[`ReviewContent component component render tests snapshot: show rubric 1`
 <div
   className="content-block"
 >
-  <ReviewErrors />
-  <Row
-    className="flex-nowrap"
+  <div
+    className="content-wrapper"
   >
-    <Col>
-      <ResponseDisplay />
-    </Col>
-  </Row>
+    <ReviewErrors />
+    <Row
+      className="flex-nowrap m-0"
+    >
+      <Col
+        className="p-0"
+      >
+        <ResponseDisplay />
+      </Col>
+    </Row>
+  </div>
 </div>
 `;
diff --git a/src/containers/Rubric/Rubric.scss b/src/containers/Rubric/Rubric.scss
index 63f53ee..afffcfc 100644
--- a/src/containers/Rubric/Rubric.scss
+++ b/src/containers/Rubric/Rubric.scss
@@ -31,8 +31,6 @@
     }
   }
 }
-.rubric-feedback {
-}
 
 .criterion-feedback {
   margin-top: 1rem;
@@ -51,6 +49,9 @@
   width: 320px;
   height: fit-content;
   max-height: 100%;
+  margin-left: map-get($spacers, 3);
+  position: sticky !important;
+  top: map-get($spacers, 1) * -1;
 
   .grading-rubric-header {
     box-shadow: 0 0 0.25rem rgba(0, 0, 0, 0.3) !important;
@@ -74,3 +75,9 @@
     opacity: .4 !important;
   }
 }
+
+@include media-breakpoint-down(sm) {
+  .grading-rubric-card {
+    margin-left: 0 !important;
+  } 
+}
\ No newline at end of file
diff --git a/src/containers/Rubric/__snapshots__/RubricFeedback.test.jsx.snap b/src/containers/Rubric/__snapshots__/RubricFeedback.test.jsx.snap
index f698267..743aad5 100644
--- a/src/containers/Rubric/__snapshots__/RubricFeedback.test.jsx.snap
+++ b/src/containers/Rubric/__snapshots__/RubricFeedback.test.jsx.snap
@@ -24,7 +24,7 @@ exports[`Rubric Feedback component snapshot feedback value is invalid 1`] = `
     as="input"
     className="rubric-feedback feedback-input"
     disabled={false}
-    floatingLabel="Add comments"
+    floatingLabel="Add comments (Optional)"
     onChange={[MockFunction this.onChange]}
     value="some value"
   />
@@ -67,7 +67,7 @@ exports[`Rubric Feedback component snapshot is graded 1`] = `
     as="input"
     className="rubric-feedback feedback-input"
     disabled={true}
-    floatingLabel="Comments"
+    floatingLabel="Comments (Optional)"
     onChange={[MockFunction this.onChange]}
     value="some value"
   />
@@ -98,7 +98,7 @@ exports[`Rubric Feedback component snapshot is grading 1`] = `
     as="input"
     className="rubric-feedback feedback-input"
     disabled={false}
-    floatingLabel="Add comments"
+    floatingLabel="Add comments (Optional)"
     onChange={[MockFunction this.onChange]}
     value="some value"
   />
diff --git a/src/containers/Rubric/messages.js b/src/containers/Rubric/messages.js
index b9561d9..dc9d2fe 100644
--- a/src/containers/Rubric/messages.js
+++ b/src/containers/Rubric/messages.js
@@ -28,12 +28,12 @@ const messages = defineMessages({
   },
   addComments: {
     id: 'ora-grading.Rubric.addComments',
-    defaultMessage: 'Add comments',
+    defaultMessage: 'Add comments (Optional)',
     description: 'Rubric comments input label',
   },
   comments: {
     id: 'ora-grading.Rubric.comments',
-    defaultMessage: 'Comments',
+    defaultMessage: 'Comments (Optional)',
     description: 'Rubric comments display label',
   },
   overallFeedbackError: {