(at around 55 mins) When Chuck Baker is talking to Lem, he points out our solar system and says it's about 20 billion miles away. The closest star to us is around 40 trillion kilometers away.
(at around 28 mins) When the soldiers remove items from Chuck's spacecraft, one of them drops an iPod, which begins loudly playing music for all to hear. iPods don't have speakers, just a headphone jack.
(at around 23 mins) As astronaut Chuck Baker gets tangled up in a planet mobile in the planetarium, his air hose becomes dislodged and his oxygen becomes depleted. Upon realizing the planet has breathable air, he removes his helmet, and the air hose is now reconnected to his suit. It is then again disconnected in the following shot.
In every instance except one, the city/town is spelled "Glipforg". On the hardware store sign, it's spelled "Glipfrog".
Skiff's braces disappear and reappear in different scenes.