Everything went well with the installation, though sudo was needed to complete the installation as expected.
However, when run the code crashes with
ImportError: cannot import name ‘ImageTk’ from ‘PIL’ (/usr/lib/python3/dist-packages/PIL/__init__.py)
There was lots more diagnostic output which can be provided on request.
Anyone any ideas? I’ve contacted the Exoclock team but without any response so far.