Alice finds a bunch of glass horses made by Charlie. Since the days of 15th century Venetian glassmaking this type of glass horse has been the definitive practice/demonstration piece for accomplished glass blowers.
Margo tells Alice that Emily gave up magic and went full "muggle". Muggle is a term for non-magic people from the Harry Potter series.
When Alice and Quentin are at the party discussing the spell they cast to speak to Charlie's ghost a poster over her left shoulder reads "Do the spirits come back?"
In the deleted scene, Eliot asks "How much longer Eugenio?" The reply in Spanish is "No sé" meaning "I don't know." The English caption incorrectly has "No say" - same pronunciation, very different meaning.