Remember that huge and stately hall furnished with grand, impressive wooden pews? Apparently that's one of the rooms that's still under construction. Instead, there's a tiny terminal with about a third of the seating capacity of now-shuttered temporary station at 21st and Wewatta. It's a little cramped. There's no wifi for customer use yet (or so they told me), and the room has very few accessible outlets. So if you've got more than, say, a half hour until the train arrives, you might as well take a walk.
If you need to stow your carry-ons, talk to the Baggage Department (to your left as you face the ticket window). For a small fee, maybe $4.00 or so, and if they are not too terribly busy, they will hold onto your items for you. But you must return to pick them up before the train actually arrives; otherwise they may be too busy loading checked luggage onto the train to give you your carry-ons back.
Leaving the terminal via the Wynkoop exit, you take the door pictured here. It's the same door you came in by if you entered from Wynkoop, but you might not have noticed how narrow that door looks from inside, how far back it's set in its frame, how oddly it's lit. It's like a closet for very slim giants. Apparently one gets to Wynkoop Street via Narnia.
Three pleasant places to pass your time await you: the Common Grounds coffee shop at 17th and Wazee), the Tattered Cover Bookstore at 16th and Wynkoop, and the Wynkoop Brewery at Wynkoop and 18th. The bookstore has a cafe, the coffee shop serves beer, and the brewery serves dinner. All three serve free wifi, useful for any last minute downloads.