Hi,
After installing CrossMap with pip, running python -c 'help("modules")' yields:
Please wait a moment while I gather a list of all available modules...
Segmentation fault (core dumped)
I suspect that src/__init__.py is misplaced. It gets installed directly in site_packages and may cause some trouble when python tries to find all modules via pkgutil.walk_packages().
Removing the file and a pip install . from the repo did solve the issue in my case.
Best,
Thomas