A couple of minor improvements:
In the copy of the css file that goes in "manager/media/styles", the path to the background image has to be "url(../images/misc/buttonbar.gif)", while in the copy that goes into "manager/media/styles/MODx" it has to be "url(../../images/misc/buttonbar.gif)"; note the extra level up.
Line 638 of the language file, or where it says
$_lang["my_account"] = "My Account";
Replace that space with a non-breaking space character. It stops that "jumping" behavior in the top menu.
In the CSS file, change the margins of the secondary menu a bit:
#nav li ul a {
border: 0;
float: left; /*ie doesn't inherit the float*/
color: #000;
padding:2px 5px;
font-weight: normal;
margin-left:-20px;
margin-right:20px;
}
That positions the menu a bit more comfortably under the main links.