Hugh Grant's character acts as if it's a given that the girls are familiar with Radiohead's "Creep"... But the use of smartphones shows the movie is happening in the present day time and the girls are in their early 20's. The song came out in 1992, close to the time of the girls birth. Especially if they came from a religiously conservative household, its very possible they would have never heard it.
A woman who was starved and in a weakened state as the captive women were wouldn't have had the strength to open the metal trap door, move the dead weight of a dead body and dump it down the shaft. Also the body was not near the base of the ladder so it would have had to have been dragged after being dropped. All that would have had to have been accomplished without making noise to alert the girls that it was happening.
When Reed uses the quotation "With great power comes great responsibility," Paxton guesses "Spider-Man (2002)," but Reed "corrects" her by saying "Voltaire." Paxton is actually correct, and there is no record of Voltaire having said anything similar.