Heyyo,
Well, I'm stumped then, cause I've got them workin' fine on my comp... try turning on waypointing mode, and check the waypoints. The one on the bottom of the ladder should be just a few inches away from the ladder, and a blue beam shooting out of it aiming towards the ladder, and the waypoint at the top of the ladder should be inside, or behind the ladder.. if not? go into the console, and type: nextmap ...usually it'll say what map you're on.. it usually doesn't know what the nextmap is, lol.
[EDIT]
Heh, guess I should mention the command to turn on n' off waypointing mode:
rcbot waypoint
I'm pretty sure that toggles it on n' off, if not? type this:
to turn it on:
rcbot waypoint on
to turn it off:
rcbot waypoint off