When Michael enters Gina's apartment the first two times, the vestibule is dark, even thought it is clearly broad daylight outside. Then the third time, after Zachary is captured and Michael and Gina return to pack her suitcases, the vestibule is well-lit from the daylight outside.
When K.I.T.T. re-activates and prepares to smash out through the back doors of the delivery truck, the car's gearshift is put into "D" (you can clearly hear three "clicks" as it shifts from "P" to "R" to "N" to "D"), yet the car then moves BACKWARDS to break through the truck's doors and exit out the back.
When Michael turns on the overhead lights at the factory, he doesn't flip the switch - he just grasps it briefly, and it stays in the "up" position that it and all the other switches in the row were originally.
When Michael and Zachery are fighting with the swords, Zachery tries to hit Michael and strikes the wooden divider. You can see more than one strike was done to the wood as there are 3 or 4 marks from the sword. These must've happened when they were practicing the scene or during other takes.
When Michael leaves the toy factory and slides over the roof of KITT, when Michael closes the drivers side door, the T-Top roof raises up slightly due to the door closing. Clearly the roof is not locked in place.
Without any evidence that Triple M Toys stole Gina's schematics, and based entirely on her speculation, Michael agrees to commit felony breaking and entering at the toy company. This is hardly something the Foundation For Law And Government would do.
When KITT crashes through the apartment and Michael punches out Cameron Zachary, the boom mic's shadow is visible on the wall on the left side.