Around the 13-minute mark, the voice from the TV uses the word "tranquilo" (Spanish for "calmed"). Since he's referring to María, he should've used "tranquila" instead.
Around the 18-minute mark, María says "hoyo pequeñita" (Spanish for "tiny hole") and "la hoyo" ("the hole"). She's using a female adjective and a female article for a male noun.
The film is presented as a modern-day restoration of a propaganda film from the 1970s, but at about 35 minutes in, a sticker of a Pokémon (1997) is seen.