While in the barn, the children hear the roar of the engines of the Destroyer flying overhead which is then shown on screen. During the time it takes for the children to cross the barn to the door, the Destroyer has somehow already landed and its men are seen sneaking around the house.
While the Galacticans would be strained to breathe in an atmosphere 20% the density of the Galactica, Michael, Sarah and the children would not have had difficulty breathing the the denser atmosphere of the Galactica. This would be no different than divers swimming around with scuba tanks. The scuba tanks would pressurize their bodies internally.
When she is first being awakened, the supposedly unconscious Sarah can be seen shifting her legs. Later, when she is being put back into the stasis tube and, again, is supposedly unconscious, she is clearly shifting around to get herself settled comfortably inside the tube.
During the nighttime outdoor scenes, you can see Hector & Vector's breath, despite both being androids.
Apollo is explaining to Michael that they have plenty of power to handle the Alliance. Right after Apollo blows up a barrel with a single shot of his laser gun, the camera pans to Michael. Just to the right of Michael's head, you can see a plane flying in the sky.
When Apollo is debating with Adama about what to do with Sara, Michael, and the children, he says, "I'm sorry, but the lives of those six people do not belong to us," but his lips say "five" not "six".