Factual error: As Ren enters Renautas and meets Emily, the word "Welcome" keeps scrolling in various languages on the screens in the background. Although hardly seen, the Hebrew is wrong, as it is reversed (text from left-to-right, as opposed to right-to-left).
Continuity mistake: When Luke and the others arrive at Gateway, there's a Smart car with its doors wide open. When they start walking and the shot changes, the doors are now hardly open. The doors keep changing position depending on the shot thereafter.