After running 86 for a night and a couple of hours more, with a few full restarts to renew it, I noticed:
- bot skips Northern Highlands again
- bot skips Cave of the Moonclan by triggering "No cave found" right after entering the Level 1 of it
- bot learned to sometimes skip Leoric's Passage, by entering the room and immediately teleporting away (pretty much like with the Cave)
- bot learned to sometimes skip even the Core of Arreat
- bot caught up a very annoying cycle-stuck in Tower of the Damned I and II somewhere around the "Move to Inner Ring" step for a couple of 180 seconds timeouts
But it still does it's job - I have 3 or 4 pets left to find, and the rainbow portion working pretty much flawlessly.
ed.: Also, all the QuesTools steps for the Old Ruins waypoint are fire off simultaneously on the arriving, hence the bot finds it way to Leoric's Passage really-really sloppy;
also, Leoric's passage, Core of Arreat, Festering Woods and probably some other locations skipping have similar simptoms, like making a slight attempt to explore, and then teleporting away only a few steps from the arriving point.