You should create a loader module that sets up the environment and loads dependencies
Like this.
https://github.com/CEXT-Dan/PyRx/blob/main/PyRxLoader/acrxEntryPoint.cpp
I use an .INI file as a fallback   

Getting error when trying follow the installation instructions

Quote

Command: (ARXLOAD "E:/Program Files/AutoCAD 2023/XDrx-API/SYS/XDRx.2023.x64.arx")
e:\program files\autocad 2023\xdrx-api\sys\xdrx.2023.x64.arx cannot find a dll or other file that it needs.
; error: ARXLOAD failed

This may happen with some versions,
try, Manually copy XDrx.x64.dll and XDrx.x86.dll in  sys directory,
to AutoCAD Install Directory

"who takes liability in those cases?"
IMHO, Liability isn’t really a thing unless you can prove negligence.  Even then, it would have to be a big dollar amount and the most likely outcome is the other party filing bankruptcy.

Interesting point regarding Python. Generally, that’s going to be open source all the way to the OS, or like in my case *CAD. An investigative IT guy can work though the chain. 
I list off all the libraries I link with. Closed source usually does the same.

Pretty sure no one went thought this list interrogating each library owner
https://prd.autocad.com/attributions/autocad2025/index.html

If its a CIV3D cogo point use this

(setq obj (vlax-ename->vla-object  (car (entsel))))
 ; vl 3d point convert to plain lisp
  (setq pt1 (vlax-safearray->list (vlax-variant-value (vlax-get-property obj "Location"))))

Quote from: ScottMC on April 26, 2024, 09:55:58 AM

With my ancient A2K, this works: (setvar "LUNITS" 2) <- for decimal

DWGUNITS can have another setting, it is optional to match AutoCAD units settings.

I would rather note that LUNITS is a sub-setting within the UNITS command, along with ANGDIR, AUNITS, ANGBASE, INSUNITS, LUPREC and AUPREC. Other system Variables that effect units are MEASUREINIT, MEASUREMENT and UNITMODE.