FTDI pins are not on the footprint because they are typically used for a connector on the arduino module itself. And having them included in the footprint would unnecessarily complicate routing as it would more or less box in the routs underneath the module.
Welcome to the wonderful land of kicad
As already mentioned, we have a kicad parts library on git hub, which we use for the mysensors components. There are setup instructions as well, so you can get started.
I think we already have a nano in our repository (I'm not near my computer at the moment so can't check).
@hek it's a python script that can be runned standalone from the terminal. By the way it's the only way I could make it work on my system. Apparently some linux versions of KiCad 5 are build without scripting support, so it crashes with segfault when this script is present in kicad's plugin folder. But as a command line script it needs only *.kicad_pcb file as an argument to work.