This is more of a suggestion for a future release than anything. From what I saw in your themes solution included in your SDK, the footer content area for the Office_Blue theme will always be horizontally aligned to the right. This makes it quite difficult to put content on the left side of the menu and ensure the content is stretched properly to prevent any sizing issues.
As a workaround I've just overridden the control template with the content presenter for the footer content set to stretch the horizontal alignment. Here's a snippet of the control template for ApplicationMenu that I had changed:
Is there any way a property could be added to the ApplicationMenu class that either exposes the ability to change the footer alignment? Perhaps something similar to FooterHorizontalAlignment and use that as a TemplateBinding with your control style setting the default value to right. That approach would allow for backward compatibility while still exposing the property for us to change if our application needs should demand. Also, the same could be said for a FooterVerticalAlignment property as well.
I can understand why it was done, but for ease of maintainability I'd prefer to not have to override the entire control template just to fix an alignment problem.
Thanks!
Jeff Winn