During the first alien attack scene, we see a group of people on the street running to escape the vaporizing rays. The camera cuts away for a few seconds, then we return to that same (repeated) scene again, with the same group of people running from the rays.
46m10s - just arrived back on Earth - dialogue as follows:- Pete: "...I know this. I seen this, man. You got post-traumatic syndrome..." During this scene, Pete's front view shows him standing on the double-yellow lines, but as the angle switches to his back view, he's suddenly re-positioned right over the single white line, nowhere near the double-yellow.
When Dr. Herbert runs out of fuel, he locates a "gas" station and uses his food coupons for by 3 gallons of gas. The Dodge pick up he is driving is a diesel (as can be seen obviously in a later scene, right after his son is taken). Gas wouldn't do him much good.
When Major Kramer is calling for the time jump coordinates to leave Mars orbit, he gets a real time response from Earth. This is impossible as it take radio signal 15 to 20 minutes, each way, to receive a transmission.
Gorman and Victoria show George Herbert a 3 legged "Squid" walker with a brain controller from the first invasion. However walkers from the first invasion had 6 legs and aliens controlled them manually.