Bug: If you travel to "The Pass Of Caradhras" using the map, you end up in "The Mines Of Moria" instead.
Other mistake: When you are in Isengard in the Hub World, notice the grey stands around the place. You will notice there are no wood planks in part of the stands. But if you stand on top of the empty space, it is clear you aren't falling through, but just standing on top of an empty space.
Bug: Return Of The King, Level 4: The Battle Of Pelennor Fields - The orc army is approaching Minas Tirith at the start of the level clip. But as the "camera" pans around, half of the orcs literally disappear.
Continuity mistake: Fellowship Of The Ring, Level 3: Weathertop - Frodo wakes up and puts out the camp fire (There is no source of light in the wide shot so it's certainly put out). But in the next shot of the hobbits, the camp fire is lit again.
Other mistake: King Theoden's aide with long orange hair announces that the King ordered that everyone make refuge for Helm's Deep. However, the king has just come out of Wormtongue's curse, and had only talked to Eowyn and Gandalf, so he couldn't have told the aide.
Continuity mistake: When Eowyn and Merry run up to defend Theoden from the Witch-king, they stop right by the dead horse's tail, but when the shot cuts to front view, they're suddenly in front of the horse's feet.
Other mistake: During the Witch-King boss fight, there is a carcass of a dead Mumak to the left. But if you go far enough to the left, you can see that the saddle is just floating there, without a Mumak carcass.
Continuity mistake: During the troll boss fights in the Black Gate level, the trolls' weapons often change from rock wedges on sticks to rock wedges on chains.
Revealing mistake: In the last midtro for level 18, "Mount Doom, " Sam reaches down to pull Frodo up the edge of the walkway. Sam's hand is seen to the top right of the screen, but a good chunk of it is missing.
Bug: When you open the "Cirith Ungol" level sign in the hub world, you get the "Mount Doom" level sign instead.
Bug: On the Mount Doom volcano (in the hub), there is a flag seen on the mountain. The flag is located as the start of the volcano next to the "Mount Doom" level sign. But if you walk back a few inches, the flag magically fades away.