Four's a CrowdGoofs
In the wedding scene, the pastor tells his wife, the organist, "Swing back into Mendelssohn again." However, she has been playing Richard Wagner's "Bridal Chorus" from Lohengrin at the time. She doesn't play Felix Mendelssohn's "Wedding March" from A Midsummer Night's Dream until the conclusion of the ceremony.
When Bob stumbles into Lorri's bedroom to evade the guards, he knocks over a table and breaks a vase. When Amy (Margaret Hamilton) comes in to check on Lorri, the broken vase and flowers on the floor have evidently disappeared or she makes no notice of them. Bob had righted the table, but had no time and was not shown cleaning up the broken vase or flowers.