Hi David Vestal,
We have prepared a sample based on your requirement 'Loading the Default Design State of the DockingManager'. In this sample, you can save the required layout in a separate XML file (e.g., DefaultLayout.xml) and load the default layout through a button click. Please refer to the attached sample and video for your reference.
Regards,
Bagavathi Perumal A
Attachment:
DockingManager_WPF_cfb1cf72.zip