Continuity mistake: When we see the flashback of Mal and Zoë first entering Serenity's cargo bay, just after Mal has bought the ship, there is a cable on the floor behind them. For a short moment, we see the cable being dragged over the grille right behind them, then the shot changes and there is nothing there at all; the only cable is much further back and lying at a completely different angle.
Continuity mistake: In the first flashback in the episode, Malcolm is showing Zoe Serenity after buying it. You can see on his left arm the stitched-up bullet hole that was from the very first episode when Mal gets shot. This episode would have taken place much later than the flashback.