dane Regarding the detection, wouldn't the position of the mount be enough, even without making a plate?
Some mounts will have the information on pier side (your mount is one of them), some mounts do not have that information -- and all you have is RA and declination information when you query the mount.
But the ZWO caters to the lowest common denominator. So it does not use that information even when available.
Another example is that some mount have pulse guiding commands, where you can guide by sending the pulse duration to the mount. Mounts that don't have that command will have to be guided by sending very slow slews, software time it, and tell the slew to stop after the software time has expired. Since there are mounts that don't have pulse command (your mount is one of them), ASIAIR appears to always use the latter, less precise, method.
As you can tell, you can point to the same equatorial coordinate (RA, declination) from either side of the pier, but one of them will probably have your instruments and pier craving into one another.
A plate solve can easily find out the side of the pier. One night, try taking an image before the target reaches Meridian, and then later take the image after a meridian flip; you will find that the image is inverted in the RA dimension.
Remember that for circumpolar stars, there are two transits through the Meridian, separated by 12 hours approximately. One transit is when the circumpolar star crosses the Meridian line between the pole and the Zenith. The other is when it crosses the meridian line between the pole and the Nadir. Just think of those two crossings as crossing the Greenwich line and the International Date Line. With the RST-135, you may have to meridian flip twice, if the darkness hours are long in winter.
Chen