For the error raised, it tells you the python executable is not in the environment variable. In that case, maybe the python is not installed properly or not installed at all. You could open Powershell on windows and simply run: python --version. This could confirm whether python is installed.
By the way, I am comfused that why it raised python error when you complie code in Arduino as you should always run C/C++ in Arduino. Could you please clarify your coding environment?
However, I’ll do my best to help based on the information you’ve shared. If any other Mac users in the community have experience with this, feel free to jump in as well.
py and python doesn*t find python in the powershell.
Why does the sketch compile with board manager 1.1.9 ?
Why are the problems on a mac and pc the same in 1.1.10 and not in 1.1.9 ?
That’s interesting I am assuming you download the Seeed nRF library from Arduino IDE directly. Maybe you could try uninstall all seeed nRF libraries in Arduino IDE, then download the seeed nRF52 board library directly from github.