CB by default does not use cookie caching of the previous tab location. To enable this you'll need to make a core edit at the below location.
IN: plugin.foundation.php
ON: Line 1071
FROM:
Code:
$this->_cbtabs = new cbTabs( 0, $_CB_framework->getUi(), null, $outputTabpaneScript );
TO:
Code:
$this->_cbtabs = new cbTabs( 1, $_CB_framework->getUi(), null, $outputTabpaneScript );
Please note we do not support core edits and typically do not provide them, but this one does not appear harmful. At any rate please use at your own risk and understand core edits WILL be lost upon upgrade of CB.