Sheba launches from the Galactica to intercept the incoming Cylons wearing a helmet with a Pegasus crest on it, from her original ship. This makes one other appearance during the ensuing battle, while otherwise she's wearing a helmet with the stylized bird crest that the Galactica's pilots wear.
Despite the damage to the Galactica from the landing bay collision, later shots of the ship show no damage at all.
When Apollo destroys the Cylon raider just before it impacts the bridge, the resulting explosive concussion hurls Adama into the railing while other crewmembers also flung around emit startled cries, some structural elements are broken and collapse, and the glass star map completely shatters and falls. The next shot is a closeup of the same map collapsing.
As the first of the "two from the first wave" Cylon fighters approaches the bow of the Galactica, a centurion says "One micron to impact coordinates." This fighter is just barely kept from impacting the bridge by Apollo twelve seconds later. As the second fighter approaches the ship's stern, missed by Starbuck, a centurion in it says "Five microns to impact," and the Cylon fighter crashes into the port landing bay only seven seconds later.
The fire retardant foam could not be fired in a straight line into the landing bay. Once released in the vacuum of space it would instantly disperse.
Assuming the fighters can be modified to carry large amounts of foam (no tanks are visible) the temperature of deep space (-270.43° Celsius) would instantly freeze the foam.
Richard Hatch is the only one who's left-handed. When he fires the lasers of his Viper, he uses his left thumb. During the boraton run on the landing bay, all three thumbs used to fire are Richard Hatch's and not Anne Lockhart's nor Dirk Benedict's.
When Apollo and Starbuck are setting the charges on the Galactica's hull, the wires holding them up are clearly visible.
The "smoke" coming under the door in the Rejuvenation Center stays on the deck, as dry ice would, instead of rising, as real (heated) smoke would.
When the room labeled "Energizer 2" blows up (seen from the door outside), the wall on the right wobbles, revealing the wooden frame holding up the wall set.
When Apollo sets the final charge and says he will use one with a magnetic base to go another way into the ship, Starbuck waves, exposing his forearm between his glove and sleeve which is impossible in outer space. This happens again when he looks back at Apollo.
The Galactica's long-range scanners show two Cylon Baseships and multiple fighters closing in. Colonel Tigh says "They're launching a major attack." Two Cylon raiders with explosives make it through - one is destroyed by Apollo but both the Bridge and one of the landing bays are seriously damaged. Scanners are destroyed and internal communications are down. The Galactica is basically crippled. At this point, the two Baseships would inevitably move in for the kill, but there's no sign of them for the rest of the episode.