Everything is open at BG. I went to the passholder previews and it was a royal mess. Everybody was complaining about the fiasco at Seaworld when they did a passhold preview at the Waterfront, BG event was much worse. The crowds were so bad that it was difficult to walk around the park, lines were around an hour for almost all rides. They even had the auxillary parking lots open and packed and were turning away from the parking lots and sending them home.
On top of the bad Haunted Lighthouse is great. No hints you will need to experience it yourself.
Also FiestaHaus is gone for ever it is now Dessert Grill. They didn't have a menu posted anywhere so I can't tell you what they did differently. I was told that they now have a blast type of show in there.