We have found that when using Internet Explorer 10 with Moodle 2.4.3, not all editing boxes are displayed when you turn editing on in the grader report. It appears to be different in each class and doesn't happen every time, but when it does, about 1/3 to 1/2 of the editing boxes are not displayed. But if you use the column or row highlight function, you can then see all of the boxes for that row/column. I've attached a screenshot of the issue and the highlight work around in the first column.
I've found that if I use the IE developer tools to change the browser document mode to IE9 standards, it resolves it. I tried adding the X-UA-Compatible meta tag to the HTTP header in the web server to force document mode to IE9, but it didn't seem to have same effect as changing it in the developer tools. Anyone have a solution?