In the intro to the final scene, the top half of the loft
doors and the bottom half are closed with no light fixture underneath. At end of the scene, during the pullout, both the top half and the bottom half of the doors are open and a blue light fixture appears underneath.
When Sasha goes into her "campaign headquarters" you can see an octagonal window in the side with solid wall underneath it but, when she enters you can see a ventilation fan in an opening right below the octagonal window. This fan nor the opening is not visible from the outside.
When Clark freezes the bees (at 26:30), the panning shot reveals the props they used to represent the dead bees are actually coffee beans.
At 8:38 there is a very visible reflection of the boom-mic when Lex closes his door.