After digging arround the generated markup of the page i was satisfied that the markup was being generated correctly, so i set about debugging the javascript, almost immediatly i spotted a discrepancy between the markup and the expected id of a tab used to call the menu functions. The JavaScript lib was expecting tabs to have an id of 'tabmenutreen' (with n being an integer), instead it was getting an id of 'menutreen'
the solution was to add a string of 'tab' to be concatenated with the menu's id on line 28 of the file /theme/page/lib.php
Before
if ($tabmenu->active) { $activated[] = $tabmenu->id; }
After
if ($tabmenu->active) {
$activated[] = 'tab'.$tabmenu->id;
}
Hope this helps put other people using this excellent course format
Tim.