The outside shot of the colony shows a red burnt orange sky with a sand storm but yet the scene inside shows bright white sunlight.
When Conor & Troi discuss the story of Humpty Dumpty and Conor says their biosphere is as fragile as an egg, he is repeating the widely held misconception that Humpty Dumpty is an egg. At no point in the nursery rhyme is it explicitly stated that Humpty Dumpty was an egg.
When Troi plays a piano with Aaron Coner, the notes heard do not match her hand movements.
Reflected in the black panel behind Geordi, as he approaches the wooden rail on the Bridge, in the opening scene.
As the landing party enters the lab to meet Dr. Hannah Bates for the first time, Will Riker, not watching where he's going, walks very fast with his head down and almost walks into the wall to the left of the doorway. He looks up at the last moment and avoids bumping into the wall, jumping through the doorway just in time. Although his character could be smiling at the occasion of meeting Dr. Bates, it sure looks like he's trying to suppress a laugh at his near miss with the wall.