During the recreation of the "King of the World" scene from Titanic, the boat is supposed to be moving but rarely progresses beyond the Sydney Opera House.
In the kitchen scene when Margaret makes Ben try Australian coffee, the number of buttons done up on her blouse keeps changing back and forth between shots.
After Bea and Ben swim to the boat and get on it, they dry out much too quickly.
When Ben and Bea first meet and he's waiting outside the bathroom, she spends several minutes trying to dry the wet spot from her jeans with the hand dryer. The wet spot on her jeans fluctuates between her attempts/positions. This can be particularly noticed when she's hanging off the sink, claiming to have just started a new internship - when her jeans seem completely dry - and a moment later when her jeans are off, being held up to the dryer, and being blown up like a balloon - when the wet spot is freshly fully wet.
At 56:13 when Ben and Margaret are on the boat chatting at the bar, Margaret's glass is half empty and when the camera angle changes it's full.
The hand prints on the glass cabinet door are not backwards; they were made by Bea's hands flipped outwards when her hands are pressed against the glass.
In the airplane scene, the economy class was filmed in a wide body aircraft but the business class is narrow body.
Claudia mispronounces Martin Scorsese's last name as "skor-SEES-ee" rather than "skor-SESS-ee". However, this is only a goof, if it is an error that the character would not have made.
When Bea is shown on the flight to Australia, she is sitting in economy of a wide-body plane with 2 aisles. However, when she sees Ben in business class, the plane only has 1 aisle, as a narrow body plane would have.
Bea and Ben meet because Bea says she desperately has to pee and Ben helps her get the key to the coffee shop restroom. She is never shown peeing/preparing to pee. However, it seems as if the actual intent is that the camera only joins her in the washroom after she has finished peeing, she is first shown refastening her pants afterwards. The toilet can be heard flushing as the scene opens.
One hour and 30 mins into movie, have a look at the green coffee cup, its there then not and then its there.
Having been filmed in Sydney, at the start of the film when Bea is standing on the street outside Ben's place, you can see cars closer to her parked in USA style but one car far up the street is parked in standard Australian style.
When Kat saw Ben on the beach and retied her bathing suit - it was clearly put on upside down. Not sure if that was part of the story and meant to happen.
The sale, possession, and use of fireworks in Australia is strictly regulated and they would not be casually lying around a house as a party novelty.