I'll add you to the Page 1 Be Our Guest List.
Great question about what time the IG opens. It opens for guests entering EPCOT around the time the park opens. I believe that it would be open for guests trying to get to the breakfast in Norway whenever the first seating is there. You would have to give your name/reservation number if it is before park opening.
As far as tours that leave from the front of the park- I'm not sure if you can get through the IG early enough for a pre-park-opening tour... The only alternate transportation to the front of the park is taxi.
There have been reports from guests who were given taxi vouchers, or credit from the resort, if they had to use taxi transport to the front of EPCOT gates when there was no other option. I don't believe this is an official policy of the resort, but it probably doesn't hurt to ask.
Could someone who is staying at the BC/YC soon ask the CMs at the IG about what time the IG opens to guests who have an early breakfast or tour, and then report back. Gracias!!!