I have modified the manager/actions/help.static.php to provide a tabbed panel that accesses a set of .php files in a new manager/help folder. You can see it in action if you log in to my site’s manager as guest, password guestuser. On one site I even added a Help icon and link on the manager’s Welcome page to make it easier for the users to find it.
At this point, the help.static.php file needs to be edited to add or remove tabs, but it’s pretty simple, each tab is just a block like
<div class="tab-page" id="tabDocsHelp">
<h2 class="tab">Documents</h2>
<script type="text/javascript">tpResources.addTabPage( document.getElementById( "tabDocsHelp" ) );</script>
<?php include './help/Documents.php'; ?>
</div>
I’m working on code to scan the help folder and generate the tabs based on the files it finds there. Then all you would need to do is add a new help file to the help folder with a name that you want as the title on the tab, like "Gallery.php".
This way you can have customized help for your clients that I’ve found already has cut my support requests to almost nothing.