edited : editor_content.css in skins folder (tinyMCE)
body, td, pre {
font-family: Arial;
font-size: 12px;
}
body {
background-color: #FFFFFF;
margin-left: 5px;
margin-top: 1em;
}
edited editor.js in program/js folder
theme_advanced_buttons1 : 'bold,italic,underline,separator,justifyleft,justifycenter,justifyright,justifyfull,separator,bullist,numlist,outdent,indent,separator,emotions,forecolor,backcolor,fontselect,fontsizeselect, separator,undo,redo,image,media',
theme_advanced_buttons2 : '',
Now the editor shows a margin on left and top. Default font is 12pt Arial and I adjusted the menubar to only 1 row (with most common elements)