Hi all...I have been trying to set up a new mission Using the litchi app. that involves trying to fly over / into a local quarry. now starting at the top of the quarry I have then selected a total of 17 way point's and 15 poi .. All looks o.k. until I try to click onto the 'spanner' / then the dotted square icon below the pencil icon,this then open's another set of 'boxes' in the bottom left of the screen..I then click on 'select all' / 'edit' .this then open up another box 'batch way point settings' Now here start my problem !!! I have set the first way point height to 82ft ( bearing in mind that I am stood at the 'top' of the quarry ) BUT when I click on the 'altitude : 82ft relative to home' that open up yet another box and try selecting 'GROUND' and then 'apply'....After several seconds delay there comes another box that show's 'ERROR failed to compute altitudes relative to ground,reason:Unknown error.' !!!! what it should be doing is working out the different height's of each way point as I fly around and into the quarry.Has Anybody got any clues or help on why this is happening ??? Many thanks for any help