Other mistake: Where the army officer is pushing the buttons on the wall panel to launch the missiles, on the both occasions you see it, the panel buckles highlighting the flimsy set.
Other mistake: When David first logs into the system after finding the right password, it shows a phone # beginning with the prefix 936. The only problem was that earlier when his computer was dialing numbers, he had not gotten to 936 yet. That was the 4th prefix and he only got through the first 3. There is no way he could have dialed that number with his computer program.