I have been going-on for some time about running scripts from the main application menu. I have now had an idea. So here goes.
1) Create a directory under C:\System\Apps (probably use the same name as the file containing the script to install)
2) Copy the contents of C:\System\Apps\Python to the directory created above leaving-out the .py files
3) Copy the script you wish to run in the directory created above
4) Create a default.py file in the directory created above which creates a namespace (as in the default.py in C:\System\Apps\Python) ane executes your script.
Not sure if the above would work but if it does I can see two issues
1) The same UID will be used for several apps (Python itself and the installed script(s))
2) Installed scripts would also be called Python and have the Python icon. Both are in the python.aif file but I have no idea how to edit that!
I would probably implement this as a function so I can add it to the standart menu in Python itself. This would be a simple modification to the default.py in C:\System\Apps\Python. There might be licensing issues relating to modifying ghe default.py in C:\System\Apps\Python.
If this works and the licensing of Python allows it then you could even make a SIS installer of this to distribute your script as an app.