Can't grade student comments if they're part of student content pages

If the instructor adds student content to a Lessons page and selects the options to have both the student content and comments on the student content graded, it is impossible to grade the student comments.

To reproduce:
Add student content to a Lessons page
Click Edit
Select 'Create gradebook entries for these' and assign 20 points to the student content
Select 'Add a comments section to each page'
Select 'Grade these comments' and assign 5 points

As student1 add some content
As student2 view student1's content and add a comment

As the instructor click on 'Show Grading Pane' and try to grade student2's comment

1) The point value displayed is not for the comment, but for the student content
2) Entering the max points for a comment and clicking Enter causes a red X to display
3) The points for the comment are not kept

Am attaching a video to show what happens