Packaging appJar Apps 
The recomended way to package appJar is to use PyInstaller
Simply download and install PyInstaller.
If everything has been installed via pip, then you should be able to package your application with the following command:
pyinstaller -F -w demo.py
If not, then you may need to specify the path of certain libraries:
pyinstaller -F -w -p <path_to_appJar> demo.py
Setting an app Icon
To set an icon for the app, include the following option:
pyinstaller -i <path_to_icon> -F -w demo.py
Including Images
To include images, include the following option:
appinstaller --add-data image.png:. -F -w demo.py
Platform Support
This has been tested & works under both Windows & Linux, although no success (yet) on OSX.
A lot more detail will be provided here, in a future releasse, on the exact process to follow to get everything built into your package.