Here is a concrete example. I am currently clouded out, but can use my MountSim mount simulator to demonstrate the problem.
The current Right Ascension of the Prime Meridian is about +10 hours. The star Dubhe has RA of about 11h, and is east of the Meridian and moving towards to west towards the Meridian (since it is in the hemisphere that is centered at the Zenith).
The star Caph has RA of about 0 hr, and is West of the meridian, and moving towards the east (since it is in the hemisphere that is centered at the Nadir).
If you start an AutoRun session, centered at Dubhe, ASIAIR will tell you that we are about 1 hour before meridian (in the Shooting Schedule window and at the bottom of the Autorun image capture window. This is correct, since we will need to perform a Meridian Flip when Dubhe crosses the Meridian.
However, if you start an AutoRun session with Caph as the target star, ASIAIR does not report that it needs any Meridian management, even though Caph will be crossing the Meridian in about two hours.
The difference is that Caph will be crossing the Meridian at a location between the pole and the Nadir. ASIAIR definitely does not know how to treat stars that are in the hemisphere that is centered at the Nadir, and thus include all circumpolar stars.
For my latitude (45.5º North), IC1396 (Elephant Trunk Nebula), NGC7000 (North America Nebula), all fall into this category at about midnight local time presently, and Heart and Soul Nebulas, M101, M51 will fall into this category early in the morning in the coming months, where auto meridian flip will fail to initiate, and the telescope will eventually smash into the pier and destroy itself.
Until you fix this problem, please warn your users not to use auto meridian flip when this could happen. Beginners who don't understand the different Meridians should not use the auto meridian flip in ASIAIR at all until this is fixed.
Chen