where do you get the option to store it? Can you name it when you store it? How do you find the file to download to the computer? .... There is a whole aspect to this that I am missing.

When I want to install a tune:
1) select one of the preset tune options
2) select to modify/make changes to the tune if desired
3) scroll through the menus to make those changes (fuel ratio / shift points / TPS adjustments.....)
4) install the tune with the changes

If I choose to later install a different tune it will ask me if I want to keep my custom changes, so I know it is saving them somewhere, but I don't see how I have direct access to it. If I say yes to keep the changes, I can further modify the tune, but will be starting from the last changes I made.

If, at any time, I return the car to stock, those custom (self-made) changes are lost as far as I know.