Go into Settings, choose the Beam room.  Choose Set up Surrounds, follow prompts.  When done, go back to the Beam room settings and choose Connect Sub.

I assume you begin with all units initialized and showing green. Are all plugged in and on-line at the same time to start?  Then set up Beam in (for instance) Living Room and add one at a time, even though Era 100’s are in stereo?

You can’t add the Era 100’s as surrounds if they are configured as stereo.  Unpair them first.  All components must be a separate room before adding the sub and surrounds.

Sorry, I meant to say I do not know how to add the Sub and the two Era after I install the Beam. 

1. Are all the other components initialized and plugged in at the same time as Beam is installed? Or are they initialized and unplugged?
2. I understand that all components have to be installed into the same room as the Beam but I do not find an option to do this that works. This should be easy. 

I already explained in the second post in this thread.