Continuity mistake: When Zorg's henchman is on the phone with Zorg and Zorg blows him up. As the smoke clears and the fires die down, the body of the henchman is still standing at the phone. (01:18:55)
Continuity mistake: As Leeloo gets off the ship at Fhloston Paradise, in one shot she is looking slightly to her left and in the next shot from behind she is looking to the right. (01:22:40)
Continuity mistake: As Korben and Ruby ascend the stairs to the opera house, during the chase shot we can see all of their backs, but both before and after there are people behind them that would make this impossible. (01:26:20)
Continuity mistake: After Leeloo fights the Mangalores in the Diva's room but then has to give the stones box to Zorg, she throws it to him with forward rotation but when the box is shown flying through the air in slow motion, it's rotating backwards. (01:29:05)
Continuity mistake: When Leeloo is fighting the Mangalores in the Diva's quarters, one of them swings at her from behind. She ducks and turns her head, and in the next shot she has turned completely around as the Mangalore throws its second punch. (01:31:25)
Continuity mistake: After the battle when Ruby is being treated we can see Korben and Vito standing together in the background in front of the security monitors talking and Vito is no longer handcuffed. Then as Ruby screams it cuts away to Korben, and we are seeing Korben standing alone near the monitors with Vito still in the process of getting his handcuffs removed and only then does he approach Korben at the monitors. (01:43:57 - 01:44:26)
Continuity mistake: When Zorg returns to the flying hotel, he kills some security guards. When Korben and the others takes his shuttle to escape, their bodies have disappeared. (01:46:15)
Continuity mistake: When they are trying to place the stones in the temple, Korben picks up either the water or air stone - by the time they get to the plinth he's holding the fire stone. (01:53:15)
Continuity mistake: The shadow of the dark planet is heading in the direction of the sun, instead of away from it, in the scene where the dark planet is approaching the temple. (01:54:55)
Continuity mistake: When Korben is activating the Fire stone, shots on his face show the match level, but shots on the other three show the match angled toward the stone. (01:57:05)
Continuity mistake: When the cops go looking for Korben and Leeloo in the fog, there are two orange light sticks hanging from the ceiling inside their car. From the outside looking in they are swinging from side to side very quickly. But from the inside looking out they are swinging from side to side very slowly.
Continuity mistake: The pre-cut piece of glass that Leeloo breaks through when she escapes is a different shape after it is broken.
Continuity mistake: When David is waiting for the priest and Leeloo before attempting to board the shuttle to Phloston Paradise, he is chewing on the nail of his index finger. The shot changes to show a different angle of him and he is now chewing on his thumbnail with no time for him to have changed position.
Continuity mistake: When Billy trips on his equipment bag, he fires the gun in an arc that goes up and slightly left. The sparks on the alien go from the center up and to the right.
Continuity mistake: When Dallas hangs the coffee pot to brew, it's hung at an angle of about 20°. A few seconds later, it's righted itself to a level position and the handle changes to silver lined.
Continuity mistake: When Leeloo is drying her shirt after being in the autowash, she is seen starting to put on the shirt and when the camera angle changes the shirt is on.
Continuity mistake: When the Diva is shot and she begins to fall, her arms are outstretched with her palms facing up. The shot changes to behind her and she continues her fall, her palms now face down.
Continuity mistake: Leeloo's face is dirty outside the building, but in the priest's apartment she's scrubbed clean.
Answer: I looked it up and it is Jill Milan. If you do a search for her, it is in her credits as an actress.