Will takes food out to Dr. Smith. The Robot tells the Robinsons that he will join the boy to ensure Will remains a safe distance from the doctor. When they arrive, the Robot allows Will to stand inches from the potentially explosive Smith.
As the Jupiter 2 tries to evade the oncoming rocket, cast members view the rocket approaching through a round view port to the left of the fixed ladder. In series one there is a door, not a window, to the left of the ladder.
When Dr. Smith sends the Robot out to check the environment, both the inner and outer airlock doors open at the same time, even though they don't know if the air is safe. Later when Smith is sent out both doors open again, even though they know the fog is harmful. This happens once again when Will goes out. The outer door should not have opened until the inner door was closed again. This would keep the planet's atmosphere from getting inside the Jupiter 2.
When the Jupiter 2 evades the missile, the planet is several miles beyond the ship. However when the missile hits the planet seconds later, the Jupiter 2 is several hundred feet from the planet surface. It would be almost impossible for the Jupiter 2 to travel that distance that quickly and experience the blast from the missile.
In the opening sequence as the Jupiter 2 is evading an exploding planet and the blast rocks the ship, the actors grab onto something large as the shop rocks back and forth. Angela Cartwright is so obviously rocking herself to simulate this effect.
The so-called radar scope gives no useful information. It just has the same moving dot pattern with no changes as the missile was approaching the Jupiter 2.
During the opening sequence, two strings guiding the Jupiter 2's landing path can be seen.
You would think that the Robot would be able to test whether or not Dr. Smith could still explode. Instead he engages the detonator to get the result, with Will standing right beside Smith.
When Tiabo captures Will and Dr. Smith, he confiscates their laser sidearms and puts them into a bulky sack. He brings them to a room, puts down the sack, and leaves them in the room with the sack. Will should have had the presence of mind to retrieve his laser from the unguarded sack and use it so that he and Dr. Smith could escape.
The Robot is able to scan the exterior of the cave to determine that the monster is no longer there, so he, Dr. Smith and Will escape. While walking back to the Jupiter 2, they pass closely by the monster and Tiabo (who are hidden behind a rock), but the Robot fails to detect them. It is reasonable to assume that the Robot would have been on the lookout for them in order to assure a successful escape.
When evading the missile from the robot planet, the same Jupiter 2 that could not afford the fuel for a course correction to return to Earth now has the fuel to go full-throttle toward the new planet to try to evade the missile.