Well we have a couple of options.
Would you be able, under python, to utilise multiple module directories?
One problem with multi users and 1 directory is that many people can modify the module willy-nilly.
Even getting multi users into someone's home directory is bad protocol, IMHO.
If you can utilise multiple directories for modules, have one, where the included modules are stored. You can allow access via permissions (777) or groups. This could be done with the install script running as root, and create and set permissions and file ownerships. This would not necessarily solve the multi user modification of modules, unless you set permissions correctly.
Then have a directory in each user's home dir and they could save modules there that they create. They can move the modules into the shared dir if needed.
This could be done to the current /usr/shared/bibleanalyzer/modules directory by setting the directory permissions to 777 on it and sub directories. This would allow user to modify and save modules threre, but I think then a public folder, say under /home/public, would be better, just to keep people out of the executables directory.
I hope I expalined that clearly