How much prep time does the monorail get?

I’m still trying to imagine how a ray can run…

I’m not sure how those two questions are related, but Batman’s very knowledgeable in pretty much all sciences, and extremely technologically talented, so I don’t see how he could not stop a runaway monorail.

Only if he could find an anchor of some sort.

No he’s not, and yes he could

If the plot demands it, then yes he can.