Hi Dwayne,
We have checked the reported problem while generating DockingManager theme resource using ThemeStudio and it is due to the incorrect color value applied for SystemDropShadowChrome element. We suggest you to remove the Color setting for SystemDropShadowChrome(Lines1168, 1301, 1363,1389 for Office2016White) in the theme files generated by WPF theme studio. We have attached the modified file for Office2016White theme and you can download it from the following location.
Theme File:
DockingManager_ThemeThis changes will not affect the theme of DockingManager control in any other way and we will include this changes in our WPF Theme Studio.
Regards,
Durga S.