When Magnum and Susan first enter the cage containing the counterfeit money, the cage's vertical middle bar is missing allowing enough space for someone to slip through. In the next scene, when Susan says Magnum is fired and slams the cage door on him the bar is now in place.
Higgins is searching the bookshelf for a book of inspirational meditations. The bookshelf is filled exclusively with reference books such as encyclopedias, multi-volume dictionaries and the like. There is no way that the highly organized Higgins, a man who during a number of previous stories was meticulously cataloguing books, would keep such a book there nor put it there by accident.