plugin works smoothly, thanks a lot for sharing.
Only one little thing to improve: a custom choice button in modal windows.
When click on "add image" link, it loads the standard WP media manager and when show the image need to click on "use as featured image" link and not in "Insert image" button, I know that you insert an alert that say to use the featured image, but should be better and less confusing, substitute the insert button and featured link with only one button : "use this image for menu link".
What you think about?
Great simple plugin!