After you've patched your calculator's firmware (and copied the launcher), it's easy to run add-on software.
Simply take the .hhk
file of the add-on, and place it into the root directory of your calculator's flash memory. Open the launcher (currently in the System app, accessed through the System > Imaginary Unit menu) and select the application you wish to launch from the list.
Tap 'Run' to launch the application.