It's a simple one- the waiting area before immigration has no windows,
but you're likely to spend most of your time at the gate area which is
very bright. ...

Do you recall whether the immigration area had Global Entry kiosks?

You can see a picture of them he
http://www.globalentry.gov/about.html

R's,
John

PS: For anyone who's about to point out that the web site has a list
of kiosk locations and Shannon's not on it, I know. But Vancouver's
not on that list either, and I've used a GE kiosk there.