Hi-
I think we have resolved the issue now.
I believe it was that PYTHONPATH was explicitly set in the ~/.bashrc file, pointing to an old (non-conda) location of Python on the system. Especially when only the base Python (which was version 3.*) was used, that was causing some confusing (because the older version pointed to was version 2.7).
Commenting out the PYTHONPATH value helped.
In each of the ~/.bashrc and ~/.cshrc, then, there was the "conda initialize" block of code for that shell, and then also a line following that with "conda activate [name of desired environment]". Then things appear to be working.
*Additional note: the PyQt4 issues in the above afni_system_check outputs are not important; we don't use PyQt4 for anything at the moment (and it also has installations in Python ver 3.*, anyways).
--pt