When Grace collapses on hearing that Victor Fox has been murdered, she drives her shopping cart into a display of Orange Slice soda. The sodas are clearly in plastic bottles, but the sound effect is of glass bottles being knocked over.
When Dirk and Grace go to the funeral home to "dress up" Victor Fox's corpse for the open-casket funeral, the funeral home manager is hesitant to allow them to enter until Dirk introduces Grace as, "This is my lawyer..." In England, Dirk would probably not have used the word "lawyer". It is more likely that he would have said, "This is my solicitor..." (although, in mitigation, the word "lawyer" is widely used, and even solicitors and barristers often describe themselves as lawyers).
When Grace and Maudey order Guinness (like Victor Fox's last drink) in the bar, the glass is filled in one go and immediately served to them. Guinness is never poured in one go. The three quarter full glass is left for a couple minutes for the froth to settle, then topped up and served. Also the color of the beer in their glasses is too light for Guinness.