Inserting data in the libraries is very easy thanks to the dialog inside Flight Master.
You can add, delete, modify the list of elements inside a library.
Only the command applicable in a situation are enabled.
To close a dialog when the close button is disabled, you need to confirm or cancel the last modification before.
Inserting data should not present any difficulties.
You already know the Air data and the Com and Nav Frequencies.
About Fix point, consider that the coordinates and the altitudes of airport and NAV point as VOR, locator , NDB are in aeronautic publications, for other you can read it directly from your map using a ruler.
Very often (always?) aeronautic maps report the geographic grid on the map
Remember that on a meridian 1 NM == 1'
And on the Equator also 1NM == 1'
...so which is the length of the World Circumference?