Setting own Locations

Early Days using the Approach S60 but I have a question searching the web cant seem to answer:

At my course there are few valleys and blind drives that carry yardage will vary depending upon where the Tee box is located so I would like add points on the course like marker posts so that I can see the yardage to these points and decide if I can reach that distance.  I can see how to set you own locations, but

1)  When you use this function are there only the pre-programmed locations such as the ones I saw?

2) Can anyone advise what the list of locations is?

3) Can you add your own locations?

4) How can you delete a self set location if it changes?

Thanks