Revealing mistake: Just before Marguerite tastes the chocolate Henry gives her, in the shot of the group walking past a pen of geese, the modern, flat, white soled shoes (likely canvas sneakers) the sisters are wearing are visible as they walk. (00:51:00)
Revealing mistake: While Danielle is up in the tree, the Gypsy punches Henry and when he flies backward and lands on his back Henry's scabbard (at his left) bends and flops around, despite the fact that his sword is sheathed, as seen in the following shots. (01:04:45)
Revealing mistake: When the Grimm brothers' carriage pulls away from the castle, after Danielle's story is told, at the top right side of the screen, there is a moving white vehicle driving toward the left side, at 01:56:42 (viewed on a tablet). Then, just before the screen fades to black, a blue car with a white top (and a couple more nondescript), can be seen parked in front of the building with a brown roof, at the bottom of the screen towards the right, at 01:56:57. (01:56:35)
Revealing mistake: When Danielle's perfectly aimed apple causes Henry to fall off the horse, his scabbard (at Henry's left) bends and flops around despite the fact that Henry's sword is supposedly in it, as seen in the following shots. (00:14:30)
Answer: There are two songs featured in the trailer: "Fable" by Robert Miles and "Mummer's Dance" by Loreena McKennitt.
Steph_Jared