Game is great, glitches are not

Ive been playing Chrono Trigger annually since it launched on SNES. The game still holds up amazingly, but it doesnt appear to work quite right on the 5S. The colours of the characters are really off whenever I enter anywhere. Everything is good on the world map, but as soon as you enter anyplace, it all starts getting funky.

BioticBibwit about CHRONO TRIGGER (Upgrade Ver.), v1.0.3