Character mistake: Error in reading of the "sextant." Mark is somewhere at 33°, but Stallone said 30° 22 minutes. I suppose they thought there were 60 minutes between marks 30 deg and 40 deg (actually there are 10°) and calculated the difference at 22 minutes.
Other mistake: When Ray attempts his first escape, he emerges from the front right side of the fire engine. When he explains how he did it, he appears too far in front of the fire engine to make it look like he was underneath it.
Factual error: When Ray figures out he is on the ship, he makes it back to his cell, creating a flood along the way, he then swims through a lot of water. When he returns to his water drenched cell and escapes with Victor, his clothes are bone dry.