Concierge has never called us. I think that is different than WDW. I make all of our plans through the Vacation Planning Office. If you stay at one of the resort hotels, standard or concierge, you can use the vacation planning office. They can make all the reservations, get all of your tickets, etc. Then, when you arrive, vacation planning has your itinerary waiting for you at check-in.
I am pretty sure that they can print up the boarding passes in the lounge. We did that when we stayed at DLH, I think. There were computers in the lounge and it was no problem. I can't remember if there are computers at the GCH lounge. sorry.
I vaguely remember that the DLH and GCH lounges open at 7:00 am. I just remember not having enough time on MM (early entry) days to go to the lounge and get to the gate. But, we went during off season, so maybe the hours are different during the busier seasons.
Maybe someone else can help me with the times.... I think they closed by 10pm, because I remember it being closed after we returned from Fantasmic.
I have found Vacation Planning to be the best source of information. I try to use the same person when I plan the vacation. Less chance of my requests falling between the cracks... If I call and she is busy, I just leave a message and then she returns my call later that day.
Hope that helps!