Hi acasagrande,
For this case, please try with my guide:
+ open plugins/editors/tinymce/jscripts/tiny_mce/themes/advanced/css/editor_ui.css, at about line 3, find following code:
.mceToolbarTop a, .mceToolbarTop a:visited, .mceToolbarTop a:hover, .mceToolbarBottom a, .mceToolbarBottom a:visited, .mceToolbarBottom a:hover {border: 0; margin: 0; padding: 0; background: transparent;}
and change to:
.mceToolbarTop a, .mceToolbarTop a:visited, .mceToolbarTop a:hover, .mceToolbarBottom a, .mceToolbarBottom a:visited, .mceToolbarBottom a:hover {border: 0; margin: 0; padding: 0; background: transparent;float: left;}