The design of the mirror shield was changed as it crescent moon and star symbol looked very similar to the Islamic emblem.
It is stated on screen and in the manual of the European release that neither Ocarina of Time
nor Master Quest
will work properly with a television set
that doesn't support a 60Hz refresh rate.
This game dumps the entire Nintendo 64 ROM to internal memory (during the initial load screen). Because of this, you could conceivably open the disc cover or even remove the disc while playing without disrupting gameplay.
Information also contributed by Late and festershinetop.