When Charlie writes Arthur Tins' name on the whiteboard he mis-spells it 'Artur'. The camera cuts away and when it cuts back, the name is correctly spelt.
When the earthquake happens, the earphones switch between being in Charlie's ears to his hand between shots.
At several points when Ted's hand is shown with the pencil going through it, you can see that the two halves are at a slight angle to one another - something that would not likely occur if the pencil was actually running through his hand and not in reality two pieces attached to both sides of his hand to make it appear so.
When Crews chases Rawls to take him down outside the apartment block, it's clear that the person he's chasing is a stuntman who has darker hair than Michael Cudlitz.