During her gymnastics routine, Leeta suddenly gains a pair of boots.
The end of the Guardian's chant differs the two times we hear it. At the end of the Lela-to-Kira transference, Lela's name is said in the final line, and Kira's is not. At the end of the Curzon-to-Odo transference, Odo's name is said, and Curzon's is not.
When Chief O'Brien is briefing Nog on the Starfleet Academy entrance exam in the Holosuite, he holds a PADD that clearly says "GO AWAY" on it. This is the same prop as used in the opening scene of Explorers (1995), given by Bashir to Jadzia to quietly tell her to leave. In the context of O'Brien and Nog of course, the text makes no sense and was certainly intended to be illegible on screen.