I have been googling for an easy way to always start the Launcher in administration mode and I came across an article from Blizzard on how to do just that.
Windows
Spoiler:
Right-click the WoW-Mania Launcher desktop application icon and select Properties.
Select the Compatibility tab.
Under Settings, check Run this program as administrator.
Click Apply.
Mac
Spoiler:
Open System Preferences.
Select Users and Groups.
Make sure your user account has the Admin option beneath it.