Question: When Michelle Stacy played Penny in the making of the film, did she pose for the drawings of Penny? Did Stacy even have to hang upside down in order to pose for the drawing of Penny held upside down by Brutus?
Chosen answer: As amusing as that would be, 99.9% chance she was not hung upside down from her undergarments.
Question: When Brutus and Nero capture Penny trying to run away, Brutus holds her by the straps on her dress. but when returning to the riverboat, Brutus holds Penny upside by her underwear. If it were possible, how would Brutus have managed to turn Penny upside down like that without releasing her and letting her run off again?
Chosen answer: It could be she got loose again when they were heading back and Brutus grabbed her again but this time by her underwear.
Question: How did the diamond get inside of the skull?
Answer: The pirate was most likely holding it when he died. As centuries past and the body decomposed, it most likely fell into the body.
Chosen answer: She may have been very upset with Penny for running away. But she may have also had a talk with her like she does much later in the movie about why she needs her for finding the diamond.