Figured out a fix for the tabs issue -- I don't know if it's 'moodlesque' or not -- but it does work this way
Seems like there is probably a function to collect Get/Post vars that I didn't see in my brief digging through the dev docs.
In .....blocks/course_menu/controls/controls.php
Change:
optional_variable($action, 'mcp');
To:
$action = $_GET['action'];
optional_variable($action, 'mcp');
That should make the tabs work correctly.
I'm also planning to work on the 'included' files that comprise each tab's content to incorporate some of the new Moodle functionality found (for example) in the 'administration' block of 1.6
Cheers,
ns