Hi
I also experienced the same problem recently.
In fact, repositry.py exists as it is create by the automatic installer at the first launch but it is delete when the crash arise.
In fact, I think there is a bug in the repositry.py script
The solution (bypass) is to launch the automatic installer.
When the repositry.py file appear, you should correct the bug before going further in the installation.
The error I found was in line 43 where I changed "versions" by "version2".
This correction should be validate by Juliette or Sebastien at HRW but it worked for me.
Here is my version
Hope this helps