Why use a Stand-Alone Application for the Hybrid Configuration Wizard?
To keep the HCW up-to-date without the risk when updating your Exchange Organization, because when it lives as a stand-alone application, it can use a stand-alone update service every time you start the wizard.
The HCW will adjust to which version of Exchange you run, but the Hybrid configured Exchange Servers needs to be within the three latest CU releases. So when we get CU 11 it will require atleast CU 9 run the stand-alone HCW.
We have improved graphics during installation, to better understand where a problem might be located: Outbound or Innboud, which have been time a consuming task to figure out in bigger projects.
Hybrid Configuration is still not working with Pre-authentication or SSL offloading when we talk about inbound traffic from Exchange Online, and Web Proxy for outbound traffic to Exchange Online is recommended to bypass for Hybrid Domain and Localhost.
If you allready have one Exchange Organization in Hybrid with your Office 365 Tenant, the Stand-Alone HCW will overwrite these configurations if you try to configure a second Exchange Organization in Hybrid With the same Office 365 Tenant. You will notice this, because configuration will be filled out according to the first Hybrid Configuration. It will read from the existing hybrid configuration, and believe you just want to edit it.