Hi Tom, unfortunately Thr Asiair Pro isn’t compatible with Celestron CGX and CGX-L despite it being listed in mount settings as an option. There are just so many bugs with it, that it fails 95% of the time. For me it fails 100% of the time, I have never had a successful night imaging with AAP and my CGX. Others have had some basic success in pockets.
my reccomendation would be to create tickets and post to this forum and hopefully, eventually ZWO will listen at some point if it gets loud enough.
but if you want to give it a shot with, the only way is to connect your Nexstar hand controller to the mount, then run atleast a 1-star alignment, more is better, then return the mount to switches, set that as HOME all via the hand controller. Now connect your AAP via USB cable to the bottom of the hand controller, in asiair app choose the CGX in mount settings, serial method. Then turn it on and it will connect. Now the mount is controlled by AAP.
from here you can fo goto’s and such; but be prepared for nightly failures when the bugs hit. The AAP will fall out of sync with the mount. Most importantly, do NOT leave your mount unattended, I promise you it will run your scope or beautiful 6200 into the tripod legs when it does an erroneous goto and thinks your object is on the other side of the planet. Crunch 🙁