Hi, Mrinmayi-

I'm doing alright, thanks, and I things are good for you, too. That is great that you are running a FMRI processing workshop!

About uber_subject.py---
[caveat---I am not the best person to answer about this, but that person is on leave for a couple days, so I will have a go...]
Firstly, I don't believe that there is currently a way to get it to run in Python 3.*, and many participants might have that, so it might be hard/impossible for them to follow along with it. It requires PyQt4 specifically, I believe, and this might only run in Python 2.7 at the moment.

I see you are using Python 2.7, and then I think the trick would be to have PyQt4 (not PyQt6, as it appears to be showing up). To manage different package things, esp. when Python is involved, I have found Conda (--> and in particular Miniconda) to be the easiest way to go---you can specify the packages+version numbers you want, and in theory they shouldn't interact with each other and you can purge them at your leisure.

Some more notes about (mini)conda specifically are---note there is both a verbose and a quick set of descriptions:
[afni.nimh.nih.gov]

I tried to make a conda environment with PyQt4, which would run uber_subject.py, and here were my results:

Failed and failed (conflict between matplotlib+numpy and PyQt4):

conda create -y -n py27_tiny_pyqt4     -c conda-forge       pyqt=4  python=2.7    matplotlib numpy
conda create -y -n py27_tiny_pyqt4     -c conda-forge       pyqt=4  python=2.7    matplotlib

Failed (Python 3.7 and PyQt4 wouldn't play nicely together):

conda create -y -n py37_tiny_pyqt4     -c conda-forge       pyqt=4  python=3.7

Worked, *but* extremely limited and won't have the nice, "pythonic" QC HTML output from afni_proc.py (just the plainer/less informative will be output---boooo):

conda create -y -n py27_tiny_pyqt4     -c conda-forge       pyqt=4  python=2.7

... so, this provides a way to open the GUI and use it, but I still might go for The Leap to afni_proc.py, parcellating the command into its component parts for understandability.

As an intro to afni_proc.py, there is this presentation given by The Bob from time to time at Bootcamps (also in the afni_handouts/ dir of the Bootcamp tarball):
[afni.nimh.nih.gov]
I have shorter+similar one from talking at the Resting State conference that I can send you, which might be useful.

--pt