Actors ignore vertical axis when following player
1)Cast levitate on self and on actor following you. 2)Fly up Following actor will run to the point right below you on the ground, and will never levitate.
However, if you force an actor to attack you instead of following, he will run after you in all three dimensions (maybe that was fixed in #1335 (closed)?)
(RM-2844 from redmine: created on 2015-08-11 by Denis Smirnov, , relates #2481 (closed))