Where does the wording under the home page menu get updated?
In the menu editor, enable "Description" on the "Screen Options" tab in th top right corner of the screen. That will allow you to see the Flex Menu options under each menu item.
Also where does the footer on the home page get updated?
You can either edit vertex/footer.php or you can place a widget in the "Footer" position. The widget is the recommended option, and the "Clean Markup" widget will allow you to use normal HTML.
I have the Shape 5 Contact form that I put in the Sign Up position in the theme but it does not seem to send out. Is there something else I need to configure?
Some servers have the PHP mail() function disabled, which would prevent the old version of the plugin from being able to send e-mails. There is a new version that you can download from the WP downloads area which now uses the wp_mail() function instead and should no longer have that problem.