User blog comment:BertH/Layout and navigation updates coming October 3/@comment-188432-20121003161350/@comment-957747-20121003194546

OK. There's a few issues here. Your "fix" simply covered up the problem of the CSS that is causing the issue. The H1 (the page title) is adding 1em of bottom margin which causes most of that gap. The rest can be fixed with a few CSS tweaks.

The other 'gap' is caused by

The big blob under the edit window is the bug I mentioned on your other comment. It shouldn't be there at all and should look the same as editing a page without a preload or newarticletext message.