Exchange 2010 iApp 1.4rc3

We are using the rc3 iApp to deploy Exchange 2010, for LTM and APM. Simple deployment, where LTM uses a single IP for all services, and APM to provide authentication for OWA on VS:443. However, the light version (new feature of iApp 1.4) is not working. Instead of being able to select the light version, or not from the APM logon page, it only displays the light version all the time.

Anyone know of a know issue around this?