it seems so that the passenger has the members name destX and destY so the if line should be if train.passenger.destX < train.x then.
By the way is there some sort of documentation for the members. I digged in your code files to find the correct variable for the tutorial.

EDIT: thanks to the hint to the wiki in the last tutorial a little bit late

and a bug if you change ( i tested smaller )resulution the screen gets smaller but not the ui.

muffel