The maggots shown on the corpse when LaSalle is photographing it are meal worms. Meal worms are found in corn and wheat flour.
At one point the computer keyboard doesn't work because there are Lego pieces blocking the keys. There is no way whatsoever for that to happen--especially not with the pieces shown falling out when the keyboard is turned upside-down and shaken. The only way that could happen is with an old type-writer.
Sitting in a park presumably far from the airport, Gibbs asks, "Where's Bishop? Our plane's about to leave." The statement reflects Hollywood culture, which is accustomed to charter flights. Federal agents have to travel commercial coach, which requires them to be at the airport hours before departure. If their plane is "about to leave" and they're not at the gate, they've already missed the flight. However, as NCIS agents they are authorized to fly military airlift (as shown several times in other episodes) and depending on the importance of the cargo being transported it is not uncommon for the aircraft commander to delay departure.
The close-up of Hanlon after being shot by Gibbs and Pride shows Hanlon's Shirt with exit-type wounds in the front from the squibs used to mimic gunshot wounds.