Have you ever downloaded a flightplan, or made your own then found you cannot save any edits you make? Here's how in Windows:
1: Download your flightplan for flightgear form whichever online flightplan creator like http://onlineflightplanner.org/ and store it in a floder on your desktop. As sometimes these flightplan creators have flaws and throw in "rogue" waypoints which will take you wildly off course!!!
2: Open this folder right click "copy"
3: RIGHT Click on your windows icon, then "right click" Run in the box type %appdata% click "OK"
4: Double click to open "Flightgear.org" folder
5: Double click to open the "export" folder
6: Transfer the items that you hit "copy" on from your desktop
Now you can edit and save the flightplans in flightgear on the "Route Manager" i.e different flight levels, change waypoints etc. DON'T FORGET once edited to click "save" and it will ask you if you want to overwrite the exsisting flightplan click "YES" And hey presto all done!
Hope this helps a few people as it took me a while to work it out