Simply run the AppMan as a one time script, as described in the page Installing Apps.

Select the "Install Models" menuitem, and a confirmation box is shown:

Click enter to intall, or exit to cancel. When the installation is fiinshed, a message is shown:

Now you can exit the script by long press '"EXIT", and enter the model selection screen:

A JustFly category has been added, containing all predefined models to select for copying.

BE AWARE that you should always make a copy before editing the models in the JustFly category. Otherwise, you will loose the original.

Have fun and

Just Fly!