Saga of a Star World (1) - S1-E1
Deliberate mistake: When the large formation of Cylons attack, the graphic that Athena is looking at shows the approaching Cylon ships as triangles, as usual. But it also shows two asterisks leading that formation, and the asterisk is the symbol for Vipers. There are NO Vipers leading the Cylons in this sequence. This graphic is a reuse of the one from the big battle at the start of the episode when Apollo and Zac were being pursued by an earlier large formation of Cylons. (02:00:30)
Deliberate mistake: When Apollo lands the Cylon fighter aboard Galactica, the view forward from behind he and Starbuck is a reuse of the same shot from the prior episode when they landed a shuttle aboard Celestra. Note the headphones they wear, then don't wear in the very next shot. (00:44:20)
The Lost Planet of the Gods (1) - S1-E4
Deliberate mistake: At the beginning, the scene in which Baltar is granted a Cylon base ship is recapped from the end of "Saga of a Star World." Only the lines are edited into a completely different order than they were before.
Greetings from Earth (2) - S1-E20
Deliberate mistake: In a wide shot Cassiopeia announces it is time for the children to go to bed, and they react with normal hoots of false shock and whining. Then the shot changes to a close-up and the same moment repeats, with the children again seemingly surprised and dismayed by the announcement. (01:02:00)
Deliberate mistake: When the Cylon ship rams the landing bay and explodes, the many quick-cut fiery destruction shots are lifted from a classic World War II film (possibly "The Guns of Navarone"). Note the stone walls (and the tanker truck just left of center in the second such shot). (00:08:05)
The Living Legend (2) - S1-E13
Deliberate mistake: When Starbuck and Apollo attack the 'flank missile launchers' of the two Cylon base stars, the shots of the launchers exploding are actually of the laser cannons on the Galactica (note the red horizontal striping on the "wall" behind each cannon). (00:44:30)
Deliberate mistake: When the Vipers make visual contact with the attacking Cylons, an exterior shot shows a large group of Cylon fighters from the front/right as they drop into view and move left to right. The rearmost ship on the left is a gold color while the rest are the usual gray. This odd effect is also seen in the first episode's first battle as well as during the last episode's last battle- an odd coincidence. The original concept for the show was to have these gold ships be the squandron leader, but showing it every week would be too expensive, so that idea was dumped and the one shot with it got used a few times without explanation. (00:05:40)