The mediaBox does not open in the correct place of the selected option. Suppose I want to update an article with select of the image intro text works fine but for the image full article which sticks half way down the page hangs.
That happens in admin page!!!!!
I'm not able to reproduce this in my tests. It could be caused on your site by a css conflict with another installed extension. That modal window is styled by Joomla core css, so I would imagine you would have the same issue if you were not using JCE.