One more thing. Can you confirm what date you installed AltAnalyze on? If you still have the original file, you can also look on the date of that file. The reason I ask is that although the code has not changed in this version, we did have some issues on Mac with getting certain libraries to link. I thought we had fixed these issues, specifically with pysam and igraph after validating on Mac's without Python, but if this is truly not working on your machine with the latest version, this is a big problem.
One thing to check would be to download the current version and simply delete the old AltAnalyze executable and replace with the current one. If the problem persists, we need to re-build and test on new machine. The alternative is to install the python version through pip install, but please check the above first. I will have others test here.