Sorry, I jump to your second post too quickly.
Anyway the problem is with ccdproc, there is already an issue for that: github.com/astropy/astropy/issues/10977
A proposed solution is to add a default value for BUNIT, I not follow further to see if the proposed solution was merged.
The keyword in this list are only "reserved", this meant they cannot be used with another signification.
But they are not mandatory and processing software must expect they are not present. In fact I never see any capture software that add this keyword because it make some sens only after calibration to some physical flux units.
Instead of adding a dummy value like "adu" it is better to report that to astro-pipelines so it can be fixed to work without this keyword.
Firecapture do not use INDI, be sure Ekos and indiserver is not started we you use Firecapture. Otherwise you will have conflict accessing the device.
Other possible problem is different ASI library version installed by INDI and Firecapture.
For CdC, be sure to follow the link to download the beta version 4.3, the version 4.2.1 comet displacement information is not compatible with the recent version of phd2.
No, I never use an Avalon mount. My response is based on the description you make on the first post.
Asiair is a proprietary software we have no idea how it work in detail, it just look like it use INDI to access the mount and other equipment.
You can use StellarMate instead if you want an open system with better support
In the example the two server communicate, this is the part "RoboFocus"@astropi of the start command of the second server, it indicate the server need to communicate with the other server on astropi when a client need to reach the focuser.
It can work if you can change the Asiair indiserver start command to add : "star2go"@star2goserver
If you cannot change the Asiair server options, this is a question only ZWO can respond.
How to chain two INDI server is described here: www.indilib.org/support/tutorials/159-in...ultiple-devices.html
Not sure how this can work with the server you are using.
You cannot run make directly, cmake is required first.
Also cmake as some interesting option, for example if using all INDI driver you can specify -DOPENSOURCEONLY=1
This prevent PHD2 to install its own libasi and libqhy, this keep your system cleaner by not having multiple version of this libraries installed.
PHD2 is easy to compile from source, see github.com/OpenPHDGuiding/phd2/wiki/BuildingPHD2OnLinux