Continuity mistake: When the security man gets tossed by the Borg, as he lands and rolls next to the far wall, his phaser falls out of the holster, and lands next to his shin. A second later, it's about two feet away from his leg.
Other mistake: When the Pakleds shoot La Forge the second time, he raises his arms a bit, seemingly in preparation to go backwards.
Continuity mistake: As La Forge prepares to transport the Pakled shoots him. He reacts, and a second later reacts again.
Continuity mistake: In the Shuttle, Q's hair is arranged in bangs on his forehead. A split second later in Ten Forward, his hair is up and back from his forehead in the familiar style.
Suggested correction: Q's powers has shown in the past that he can change his looks in an instance, as well as his location and anyone else he chooses. This is precisely what happens here.
Other mistake: After Riker turns off Data, Data slumps forward. After being in that position, and after the cut scene, Data's head twitches slightly.
Revealing mistake: When looking at Kolrami, the line between his make up and actual skin tone can be seen between his scalp, hairline, and the back of his neck.
Continuity mistake: When checking Ian's pulse, Pulaski reaches out with her left hand, but her right arm retracts after the angle change.
Where Silence Has Lease - S2-E2
Continuity mistake: When Riker and Worf are beamed off the Yomato, Riker is on the left of Worf. When they materialize, Riker is on Worf's right.