Hi scottnj,
Yes it seems that BE is doing installation when you add license keys to your BE server.
But dont worry, whenever you add license keys or install additional options, BE runs "installation" wizard which adds licenses and so on.
Only thing you need to consider is when running license add wizard, because the wizard restarts BE's services on media server. So dont add licenses or options when running backup jobs or BE maintenance task.
Edit: So when adding options or license keys, you dont loose any settings.