In "view xx submitted assignments", as admin, click on "grade" link:

• one popup is opened.
• introduce one grade and one comment.
• PROBLEM C: It's impossible to add images in the comments editor.
• PROBLEM D: The comments field has not its corresponding "submissioncommentformat" field.
• Save changes
• PROBLEM E: The popup remains with "horrible" page with blocks and message "Changes saved. This window should close automatically. If not, please close it now"
• Close the popup manually. Reload the "view xx submitted assignments" pages. Both the comment and the grade have been saved properly.
• PROBLEM F: The comment in that page shows plain text so you can see the HTML (if quick grading is enabled).