Visible crew/equipment: When Murdoch puffs by a field, a stage light is reflected off the coach's windows.
Deliberate mistake: When Thomas goes by the level crossing, a close up of Thomas is shown but it's the same footage from season 1, only flipped. Because of this, Thomas' number is mirrored.
Visible crew/equipment: When the banner hits Gordon, in the next shot, a scaffold is very visible in the trees on the right. (Visible in Wide screen version only).
Fergus Breaks the Rules - S7-E18
Continuity mistake: When Fergus runs away, his taillamp is on his right side. When he hides in the siding, his lamp is on the left side.
Revealing mistake: When Toby tells the Fat Controller about the broken windmill, his driver's head appears to have been digitally added.
Continuity mistake: Thomas was pushing 4 trucks and a brake van, but when the trucks are laughing at Thomas, there are 2 trucks and a brake van. A truck also gains a face.
Fergus Breaks the Rules - S7-E18
Revealing mistake: A wire is under Fergus when he arrives at the smelter's.
Visible crew/equipment: A crew member is visible on the left side of the screen when Skarloey notices the hot air balloon is about to crash.
Snow Engine - S7-E14
Other mistake: Before Oliver crashes, no-one appears to be inside his cab in a shot of him passing a crossing.
Answer: He was in the water.