I was there a week ago Sunday. Someone told me Cynthia comes out and she's great, but nobody else. That day, Cynthia didn't come out but Maggie Gyllenhaal and Ewan McGregor did. Maybe they alternate or maybe this person was clueless. In any event, they both had black SUVs there for them, so that should be easy to tell. They actually have a barricade, which is not often the case at American Airlines. Both signed Playbills but did not pose for photos.
There are several pictures of Ewan McGregor at the stage-door on Instagram. Looking up a celebrity's name in the hashtags on Instagram is a good way to find out if they sign and/or pose for pictures at the stage-door.
Yes. I got all of the four leads. Though we waited until 11:00 for Maggie in the freezing cold. And I'm not even a fan. Just wanted to have the signature of the great Cynthia Nixon. And Ms. Nixon even posed for pictures! (I didn't bother her though) The rest didn't. (josh wouldn't also have minded if somebody asked him though. He seemed like a nice guy) Both Ewan and Maggie refused. (If you wanted the kids' signature all were happy to sign the playbills too)
I didn't stay for Maggie as I needed to catch a train and she was quite late (and I also didn't really care about getting her signature), but Ewan was very nice, polite and willing to talk to you for a bit.
Everyone was nice. Josh I think was the nicest of the cast. Ewan was very polite, Cynthia was very accommodating, and Maggie was very late but courteous. (But I think no once can beat Audra McDonald and Jessie Mueller - for me they are still the most gracious, down-to-earth, very warm and caring, very accommodating, and, although I don't know them personally, I think they are just the loveliest human beings on Broadway.)