Corrected entry: When Harry buys all the sweets from the cart on the train he places them on the chair beside him. But there are clearly more sweets on the chair then there were on the trolley.
Corrected entry: At the end of the movie Hagrid gives Harry the photo album. After Harry looks at it and tells Hagrid goodbye, he walks back to the train with his hands at his side and there is no sign of the album in either hand.
Correction: He could just put in one of the pockets of his robes.
Corrected entry: When Hagrid picks up the Philosopher's Stone from Gringotts, he tells Harry "best not mention this to anyone". But as soon as Harry becomes suspicious about Snape, he begins discussing the fact that Hagrid emptied the vault in full earshot of all and sundry, at the dinner table.
Correction: Harry can trust Ron and Hermione, and being the kind of guy Harry is, he would tell those two anything.
Correction: He simply gave the woman a handful of money. If he had more money than there was candy, the lady could simply get (or magic) more.